Q: Is 421,808 a Prime Number?
A: No, 421,808 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 421808 can be evenly divided by 1 2 4 8 16 41 82 164 328 643 656 1,286 2,572 5,144 10,288 26,363 52,726 105,452 210,904 and 421,808, with no remainder.
Since 421,808 cannot be divided by just 1 and 421,808, it is not a prime number.