Q: Is 21,585 a Prime Number?
A: No, 21,585 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 21585 can be evenly divided by 1 3 5 15 1,439 4,317 7,195 and 21,585, with no remainder.
Since 21,585 cannot be divided by just 1 and 21,585, it is not a prime number.