Q: Is 728,221 a Prime Number?
A: No, 728,221 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 728221 can be evenly divided by 1 13 31 139 169 403 1,807 4,309 5,239 23,491 56,017 and 728,221, with no remainder.
Since 728,221 cannot be divided by just 1 and 728,221, it is not a prime number.