Q: Is 21,648 a Prime Number?
A: No, 21,648 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 21648 can be evenly divided by 1 2 3 4 6 8 11 12 16 22 24 33 41 44 48 66 82 88 123 132 164 176 246 264 328 451 492 528 656 902 984 1,353 1,804 1,968 2,706 3,608 5,412 7,216 10,824 and 21,648, with no remainder.
Since 21,648 cannot be divided by just 1 and 21,648, it is not a prime number.