Q: Is 21,105 a Prime Number?
A: No, 21,105 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 21105 can be evenly divided by 1 3 5 7 9 15 21 35 45 63 67 105 201 315 335 469 603 1,005 1,407 2,345 3,015 4,221 7,035 and 21,105, with no remainder.
Since 21,105 cannot be divided by just 1 and 21,105, it is not a prime number.