1, 3, 7, 19, 21, 57, 133, and 399. The prime factors of 399 are 3, 7, and 19.
399 is not prime as it has more than two factors which are 1 and itself as it has many other combinations of numbers to resolve the question so no 399 is not prime
399 is not a prime number because it has more than two factors which can be shown by the prime factorization of 399 i.e. P.F. of 399 = 3x7x19.
3 x 7 x 19 = 399
The factors of 399 are: 1, 3, 7, 19, 21, 57, 133, 399.
1, 3, 5, 7, 15, 19, 21, 35, 57, 95, 105, 133, 285, 399, 665, 1995 3, 5, 7 and 19 are prime.
The prime factorization of 399 is 3 x 7 x 19. 21 wouldn't be included since it isn't a prime number.
1, 3, 7, 19, 21, 57, 133, 399
1, 3, 7, 19, 21, 57, 133, 399
399 = 3 * 7 * 19
The common factors are: 1, 3
Prime factors are factors that are also prime numbers.