Question

Find if 289 is a prime number.

Answer 1

To be 289 a prime number, it would have been required that 289 has only two divisors, i.e., itself and 1. However, 289 is a semiprime (also called biprime or 2-almost-prime), because it is the product of a two non-necessarily distinct prime numbers. Indeed, 289 = 17 x 17, where 17 is a prime number