Q: Is 721,438 a Prime Number?
A: No, 721,438 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 721438 can be evenly divided by 1 2 163 326 2,213 4,426 360,719 and 721,438, with no remainder.
Since 721,438 cannot be divided by just 1 and 721,438, it is not a prime number.