Q: Is 420,643 a Prime Number?
A: No, 420,643 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 420643 can be evenly divided by 1 547 769 and 420,643, with no remainder.
Since 420,643 cannot be divided by just 1 and 420,643, it is not a prime number.