19 is the only one that only has 1 and itself as factors. It is the Prime number.
19 is the prime number.
19 is prime.
9 is the prime number.
19 is the prime number.
19 is the prime number out of the provided choices.
19
19
Any number whose digits total 3, 6 or 9 is divisible by 3 and, therefore, not prime.
It is19 because it has only two factors
19 is prime.
They are 13 and 19 which are prime numbers
It is 1 because 19 is a prime number