Q: Is 631,643 a Prime Number?
A: Yes, 631,643 is a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 631643 can be evenly divided by 1 and 631,643, with no remainder.
Since 631,643 can be divided by just 1 and 631,643, it is a prime number.