Q: Is 421,509 a Prime Number?
A: No, 421,509 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 421509 can be evenly divided by 1 3 11 33 53 159 241 583 723 1,749 2,651 7,953 12,773 38,319 140,503 and 421,509, with no remainder.
Since 421,509 cannot be divided by just 1 and 421,509, it is not a prime number.