Q: Is 639,628 a Prime Number?
A: No, 639,628 is not a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 639628 can be evenly divided by 1 2 4 11 22 44 14,537 29,074 58,148 159,907 319,814 and 639,628, with no remainder.
Since 639,628 cannot be divided by just 1 and 639,628, it is not a prime number.