31 is a prime number.
31
31
31 and 41 are prime numbers because they have only two factors
The prime numbers greater than 21 are 23, 29, 31, 37, 41, 43, 47, etc.
31 is a prime number.
21 is not a prime.
31
31
31
31 is the only one that has only two factors: 1 and itself. It is the prime number.
31 and 41 are prime numbers because they have only two factors
21 = 3 * 7 31 = 31 (it is prime) 100 = 2 * 2 * 5 * 5
The prime numbers greater than 21 are 23, 29, 31, 37, 41, 43, 47, etc.
31 and 61 are prime, the rest composite.
It is: B 31 is a prime number because it has only two factors which are itself and one
31 is a prime number