Q: Is 640,791 a Prime Number?
A: No, 640,791 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 640791 can be evenly divided by 1 3 9 27 81 243 293 729 879 2,187 2,637 7,911 23,733 71,199 213,597 and 640,791, with no remainder.
Since 640,791 cannot be divided by just 1 and 640,791, it is not a prime number.