Q: Is 21,655 a Prime Number?
A: No, 21,655 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 21655 can be evenly divided by 1 5 61 71 305 355 4,331 and 21,655, with no remainder.
Since 21,655 cannot be divided by just 1 and 21,655, it is not a prime number.