Q: Is 491,643 a Prime Number?
A: No, 491,643 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 491643 can be evenly divided by 1 3 9 27 131 139 393 417 1,179 1,251 3,537 3,753 18,209 54,627 163,881 and 491,643, with no remainder.
Since 491,643 cannot be divided by just 1 and 491,643, it is not a prime number.