Q: Is 400,509 a Prime Number?
A: No, 400,509 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 400509 can be evenly divided by 1 3 9 44,501 133,503 and 400,509, with no remainder.
Since 400,509 cannot be divided by just 1 and 400,509, it is not a prime number.