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2026-01-01
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<p>Last updated on<strong>August 5, 2025</strong></p>
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<p>Last updated on<strong>August 5, 2025</strong></p>
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<p>The numbers that have only two factors, which are 1 and itself, are called prime numbers. For encryption, computer algorithms, barcode generation, prime numbers are used. In this topic, we will be discussing whether 138 is a prime number or not.</p>
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<p>The numbers that have only two factors, which are 1 and itself, are called prime numbers. For encryption, computer algorithms, barcode generation, prime numbers are used. In this topic, we will be discussing whether 138 is a prime number or not.</p>
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<h2>Is 138 a Prime Number?</h2>
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<h2>Is 138 a Prime Number?</h2>
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<p>There are two<a>types of numbers</a>, mostly -</p>
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<p>There are two<a>types of numbers</a>, mostly -</p>
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<p><a>prime numbers</a>and<a>composite numbers</a>, depending on the number of<a>factors</a>.</p>
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<p><a>prime numbers</a>and<a>composite numbers</a>, depending on the number of<a>factors</a>.</p>
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<p>A prime number is a<a>natural number</a>that is divisible only by 1 and itself.</p>
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<p>A prime number is a<a>natural number</a>that is divisible only by 1 and itself.</p>
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<p>For example, 3 is a prime number because it is divisible by 1 and itself.</p>
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<p>For example, 3 is a prime number because it is divisible by 1 and itself.</p>
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<p>A composite number is a positive number that is divisible by more than two numbers.</p>
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<p>A composite number is a positive number that is divisible by more than two numbers.</p>
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<p>For example, 6 is divisible by 1, 2, 3, and 6, making it a composite number.</p>
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<p>For example, 6 is divisible by 1, 2, 3, and 6, making it a composite number.</p>
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<p>Prime numbers follow a few properties like: </p>
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<p>Prime numbers follow a few properties like: </p>
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<ul><li>Prime numbers are positive numbers always<a>greater than</a>1. </li>
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<ul><li>Prime numbers are positive numbers always<a>greater than</a>1. </li>
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<li>2 is the only even prime number. </li>
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<li>2 is the only even prime number. </li>
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<li>They have only two factors: 1 and the number itself. </li>
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<li>They have only two factors: 1 and the number itself. </li>
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<li>Any two distinct prime numbers are<a>co-prime numbers</a>because they have only one common factor, which is 1.</li>
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<li>Any two distinct prime numbers are<a>co-prime numbers</a>because they have only one common factor, which is 1.</li>
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</ul><p>As 138 has more than two factors, it is not a prime number.</p>
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</ul><p>As 138 has more than two factors, it is not a prime number.</p>
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<h2>Why is 138 Not a Prime Number?</h2>
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<h2>Why is 138 Not a Prime Number?</h2>
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<p>The characteristic<a>of</a>a prime number is that it has only two divisors: 1 and itself. Since 138 has more than two factors, it is not a prime number. A few methods are used to distinguish between prime and composite numbers: </p>
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<p>The characteristic<a>of</a>a prime number is that it has only two divisors: 1 and itself. Since 138 has more than two factors, it is not a prime number. A few methods are used to distinguish between prime and composite numbers: </p>
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<ul><li>Counting Divisors Method </li>
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<ul><li>Counting Divisors Method </li>
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<li>Divisibility Test </li>
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<li>Divisibility Test </li>
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<li>Prime Number Chart </li>
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<li>Prime Number Chart </li>
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<li>Prime Factorization</li>
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<li>Prime Factorization</li>
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</ul><h3>Using the Counting Divisors Method</h3>
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</ul><h3>Using the Counting Divisors Method</h3>
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<p>The method in which we count the number of divisors to categorize the numbers as prime or composite is called the counting divisors method. Based on the count of the divisors, we categorize numbers as prime or composite. If there is a total count of only 2 divisors, then the number would be prime. If the count is more than 2, then the number is composite. Let's check whether 138 is prime or composite.</p>
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<p>The method in which we count the number of divisors to categorize the numbers as prime or composite is called the counting divisors method. Based on the count of the divisors, we categorize numbers as prime or composite. If there is a total count of only 2 divisors, then the number would be prime. If the count is more than 2, then the number is composite. Let's check whether 138 is prime or composite.</p>
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<p><strong>Step 1:</strong>All numbers are divisible by 1 and itself.</p>
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<p><strong>Step 1:</strong>All numbers are divisible by 1 and itself.</p>
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<p><strong>Step 2:</strong>Divide 138 by 2. It is divisible by 2, so 2 is a factor of 138.</p>
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<p><strong>Step 2:</strong>Divide 138 by 2. It is divisible by 2, so 2 is a factor of 138.</p>
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<p><strong>Step 3:</strong>Divide 138 by 3. It is divisible by 3, so 3 is a factor of 138.</p>
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<p><strong>Step 3:</strong>Divide 138 by 3. It is divisible by 3, so 3 is a factor of 138.</p>
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<p><strong>Step 4:</strong>You can simplify checking divisors up to 138 by finding the root value. We then need to only check divisors up to that root value.</p>
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<p><strong>Step 4:</strong>You can simplify checking divisors up to 138 by finding the root value. We then need to only check divisors up to that root value.</p>
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<p>Since 138 has more than 2 divisors, it is a composite number.</p>
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<p>Since 138 has more than 2 divisors, it is a composite number.</p>
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<h3>Using the Divisibility Test Method</h3>
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<h3>Using the Divisibility Test Method</h3>
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<p>We use a<a>set</a>of rules to check whether a number is divisible by another number completely or not. It is called the Divisibility Test Method. </p>
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<p>We use a<a>set</a>of rules to check whether a number is divisible by another number completely or not. It is called the Divisibility Test Method. </p>
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<p><strong>Divisibility by 2:</strong>The number in the one's<a>place value</a>is 8. Since 8 is an<a>even number</a>, 138 is divisible by 2. </p>
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<p><strong>Divisibility by 2:</strong>The number in the one's<a>place value</a>is 8. Since 8 is an<a>even number</a>, 138 is divisible by 2. </p>
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<p><strong>Divisibility by 3:</strong>The<a>sum</a>of the digits in the number 138 is 12. Since 12 is divisible by 3, 138 is also divisible by 3. </p>
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<p><strong>Divisibility by 3:</strong>The<a>sum</a>of the digits in the number 138 is 12. Since 12 is divisible by 3, 138 is also divisible by 3. </p>
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<p><strong>Divisibility by 5:</strong>The unit’s place digit is 8. Therefore, 138 is not divisible by 5. </p>
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<p><strong>Divisibility by 5:</strong>The unit’s place digit is 8. Therefore, 138 is not divisible by 5. </p>
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<p><strong>Divisibility by 7:</strong>The last digit in 138 is 8. Double the last digit (8 × 2 = 16). Subtract it from the rest of the number (13 - 16 = -3). Since -3 is not divisible by 7, 138 is not divisible by 7.</p>
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<p><strong>Divisibility by 7:</strong>The last digit in 138 is 8. Double the last digit (8 × 2 = 16). Subtract it from the rest of the number (13 - 16 = -3). Since -3 is not divisible by 7, 138 is not divisible by 7.</p>
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<p><strong>Divisibility by 11:</strong>In 138, the sum of the digits in odd positions is 1 + 8 = 9, and the sum of the digits in even positions is 3. The difference is 6, which is not divisible by 11. So, 138 is not divisible by 11.</p>
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<p><strong>Divisibility by 11:</strong>In 138, the sum of the digits in odd positions is 1 + 8 = 9, and the sum of the digits in even positions is 3. The difference is 6, which is not divisible by 11. So, 138 is not divisible by 11.</p>
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<p>Since 138 is divisible by numbers other than 1 and itself, it has more than two factors. Therefore, it is a composite number.</p>
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<p>Since 138 is divisible by numbers other than 1 and itself, it has more than two factors. Therefore, it is a composite number.</p>
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<h3>Using Prime Number Chart</h3>
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<h3>Using Prime Number Chart</h3>
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<p>The prime number chart is a tool created by using a method called “The Sieve of Eratosthenes.” In this method, we follow the following steps:</p>
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<p>The prime number chart is a tool created by using a method called “The Sieve of Eratosthenes.” In this method, we follow the following steps:</p>
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<p><strong>Step 1:</strong>Write numbers from 1 to 150 in rows and columns.</p>
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<p><strong>Step 1:</strong>Write numbers from 1 to 150 in rows and columns.</p>
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<p><strong>Step 2:</strong>Leave 1 without coloring or crossing, as it is neither prime nor composite.</p>
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<p><strong>Step 2:</strong>Leave 1 without coloring or crossing, as it is neither prime nor composite.</p>
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<p><strong>Step 3:</strong>Mark 2 because it is a prime number and cross out all the<a>multiples</a>of 2.</p>
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<p><strong>Step 3:</strong>Mark 2 because it is a prime number and cross out all the<a>multiples</a>of 2.</p>
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<p><strong>Step 4:</strong>Mark 3 because it is a prime number and cross out all the multiples of 3.</p>
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<p><strong>Step 4:</strong>Mark 3 because it is a prime number and cross out all the multiples of 3.</p>
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<p><strong>Step 5:</strong>Repeat this process until you reach the table consisting of marked and crossed boxes, except 1. Through this process, we will have a list of prime numbers from 1 to 150. The list includes 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, etc.</p>
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<p><strong>Step 5:</strong>Repeat this process until you reach the table consisting of marked and crossed boxes, except 1. Through this process, we will have a list of prime numbers from 1 to 150. The list includes 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, etc.</p>
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<p>138 is not present in the list of prime numbers, so it is a composite number.</p>
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<p>138 is not present in the list of prime numbers, so it is a composite number.</p>
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<h3>Using the Prime Factorization Method</h3>
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<h3>Using the Prime Factorization Method</h3>
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<p>Prime factorization is a process of breaking down a number into<a>prime factors</a>. Then multiply those factors to obtain the original number.</p>
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<p>Prime factorization is a process of breaking down a number into<a>prime factors</a>. Then multiply those factors to obtain the original number.</p>
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<p><strong>Step 1:</strong>We can write 138 as 2 × 69.</p>
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<p><strong>Step 1:</strong>We can write 138 as 2 × 69.</p>
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<p><strong>Step 2:</strong>In 2 × 69, 69 is a composite number. Further, break 69 into 3 × 23.</p>
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<p><strong>Step 2:</strong>In 2 × 69, 69 is a composite number. Further, break 69 into 3 × 23.</p>
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<p><strong>Step 3:</strong>Now we get the<a>product</a>consisting of only prime numbers.</p>
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<p><strong>Step 3:</strong>Now we get the<a>product</a>consisting of only prime numbers.</p>
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<p>Hence, the prime factorization of 138 is 2 × 3 × 23.</p>
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<p>Hence, the prime factorization of 138 is 2 × 3 × 23.</p>
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<h2>Common Mistakes to Avoid When Determining if 138 is Not a Prime Number</h2>
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<h2>Common Mistakes to Avoid When Determining if 138 is Not a Prime Number</h2>
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<p>Children might have some misconceptions about prime numbers when they are learning about them. Here are some mistakes that might be made by children.</p>
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<p>Children might have some misconceptions about prime numbers when they are learning about them. Here are some mistakes that might be made by children.</p>
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<h2>FAQ on Is 138 a Prime Number?</h2>
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<h2>FAQ on Is 138 a Prime Number?</h2>
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<h3>1.Is 138 a perfect square?</h3>
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<h3>1.Is 138 a perfect square?</h3>
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<h3>2.What is the sum of the divisors of 138?</h3>
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<h3>2.What is the sum of the divisors of 138?</h3>
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<p>The sum of the divisors of 138 is 288.</p>
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<p>The sum of the divisors of 138 is 288.</p>
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<h3>3.What are the factors of 138?</h3>
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<h3>3.What are the factors of 138?</h3>
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<p>138 is divisible by 1, 2, 3, 6, 23, 46, 69, and 138, making these numbers the factors.</p>
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<p>138 is divisible by 1, 2, 3, 6, 23, 46, 69, and 138, making these numbers the factors.</p>
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<h3>4.What are the closest prime numbers to 138?</h3>
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<h3>4.What are the closest prime numbers to 138?</h3>
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<p>137 and 139 are the closest prime numbers to 138.</p>
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<p>137 and 139 are the closest prime numbers to 138.</p>
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<h3>5.What is the prime factorization of 138?</h3>
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<h3>5.What is the prime factorization of 138?</h3>
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<p>The prime factorization of 138 is 2 × 3 × 23.</p>
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<p>The prime factorization of 138 is 2 × 3 × 23.</p>
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<h2>Important Glossaries for "Is 138 a Prime Number"</h2>
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<h2>Important Glossaries for "Is 138 a Prime Number"</h2>
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<ul><li><strong>Composite numbers:</strong>Natural numbers greater than 1 that are divisible by more than 2 numbers are called composite numbers. For example, 12 is a composite number because 12 is divisible by 1, 2, 3, 4, 6, and 12.</li>
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<ul><li><strong>Composite numbers:</strong>Natural numbers greater than 1 that are divisible by more than 2 numbers are called composite numbers. For example, 12 is a composite number because 12 is divisible by 1, 2, 3, 4, 6, and 12.</li>
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</ul><ul><li><strong>Prime numbers:</strong>Natural numbers greater than 1 that have no divisors other than 1 and itself. For example, 7 is a prime number.<strong></strong></li>
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</ul><ul><li><strong>Prime numbers:</strong>Natural numbers greater than 1 that have no divisors other than 1 and itself. For example, 7 is a prime number.<strong></strong></li>
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</ul><ul><li><strong>Factors:</strong>The numbers that divide the number exactly without leaving a remainder are called factors. For example, the factors of 4 are 1, 2, and 4 because they divide 4 completely.</li>
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</ul><ul><li><strong>Factors:</strong>The numbers that divide the number exactly without leaving a remainder are called factors. For example, the factors of 4 are 1, 2, and 4 because they divide 4 completely.</li>
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</ul><ul><li><strong>Divisibility rules:</strong>Guidelines used to determine if one number is divisible by another without performing full division.</li>
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</ul><ul><li><strong>Divisibility rules:</strong>Guidelines used to determine if one number is divisible by another without performing full division.</li>
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</ul><ul><li><strong>Prime factorization:</strong>The process of expressing a number as the product of its prime factors. For example, the prime factorization of 18 is 2 × 3 × 3.</li>
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</ul><ul><li><strong>Prime factorization:</strong>The process of expressing a number as the product of its prime factors. For example, the prime factorization of 18 is 2 × 3 × 3.</li>
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</ul><p>What Are Prime Numbers? 🔢✨ | Easy Tricks & 🎯 Fun Learning for Kids | ✨BrightCHAMPS Math</p>
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</ul><p>What Are Prime Numbers? 🔢✨ | Easy Tricks & 🎯 Fun Learning for Kids | ✨BrightCHAMPS Math</p>
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<h2>Hiralee Lalitkumar Makwana</h2>
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<h2>Hiralee Lalitkumar Makwana</h2>
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<h3>About the Author</h3>
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<h3>About the Author</h3>
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<p>Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.</p>
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<p>Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.</p>
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<h3>Fun Fact</h3>
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<h3>Fun Fact</h3>
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<p>: She loves to read number jokes and games.</p>
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<p>: She loves to read number jokes and games.</p>