Q: Is 421,405 a Prime Number?
A: No, 421,405 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 421405 can be evenly divided by 1 5 271 311 1,355 1,555 84,281 and 421,405, with no remainder.
Since 421,405 cannot be divided by just 1 and 421,405, it is not a prime number.