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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.
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Is number 21 prime or composite?
number 21 is prime
Is the prime number 21 is a prime number?
21 is a composite number, not a prime, having prime factors 3x7.
Is 21 and 31 a prime number?
21 is composite number that is a multiple of 3. 31 is a prime number.
Is 21 a factor of 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.
Is the number 441 a prime number?
no, 21*21=441
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