Q: Is 640,671 a Prime Number?
A: No, 640,671 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 640671 can be evenly divided by 1 3 213,557 and 640,671, with no remainder.
Since 640,671 cannot be divided by just 1 and 640,671, it is not a prime number.