Q: Is 421,604 a Prime Number?
A: No, 421,604 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 421604 can be evenly divided by 1 2 4 105,401 210,802 and 421,604, with no remainder.
Since 421,604 cannot be divided by just 1 and 421,604, it is not a prime number.