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21 is the product of two prime numbers, three and seven.

A Prime number is defined as a number divisible only by one or itself.

So ... NO ... 21 is not a prime number.

Q: Is 21 seven a prime number?

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number 21 is prime

21 is a composite number, not a prime, having prime factors 3x7.

21 is composite number that is a multiple of 3. 31 is a prime number.

No. The only factors of a prime number are 1 and itself. The only way that 21 could be a factor of a prime number is if it were a prime number, but it is not because 21 is also divisible by 3 and 7.

no, 21*21=441

Related questions

number 21 is prime

21 is a composite number, not a prime, having prime factors 3x7.

The number seven is 7 which is a Prime number.

11 is a prime number but 21 is not a prime number as it is divisible by 3.

A prime number is any integer evenly divisible by only itself, and the number 1. Since 21 is divisible by 3 and 7, it is a composite number, not a prime number.No, 21 is not a prime number.21 is divisible by 1, 3, 7, & 21No. 21=3*7

Yes seven is a prime number and the only numbers that will go in to seven is one and seven.

21 is composite number that is a multiple of 3. 31 is a prime number.

No. The only factors of a prime number are 1 and itself. The only way that 21 could be a factor of a prime number is if it were a prime number, but it is not because 21 is also divisible by 3 and 7.

3 * 7 = 21 21 is not prime

21 is a composite number

no, 21*21=441

Who says it is? 21 is a composite number!