Q: Is 21,165 a Prime Number?
A: No, 21,165 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 21165 can be evenly divided by 1 3 5 15 17 51 83 85 249 255 415 1,245 1,411 4,233 7,055 and 21,165, with no remainder.
Since 21,165 cannot be divided by just 1 and 21,165, it is not a prime number.