Q: Is 121,605 a Prime Number?
A: No, 121,605 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 121605 can be evenly divided by 1 3 5 11 15 33 55 67 121 165 201 335 363 605 737 1,005 1,815 2,211 3,685 8,107 11,055 24,321 40,535 and 121,605, with no remainder.
Since 121,605 cannot be divided by just 1 and 121,605, it is not a prime number.