Q: Is 505,665 a Prime Number?
A: No, 505,665 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 505665 can be evenly divided by 1 3 5 9 15 17 45 51 85 153 255 661 765 1,983 3,305 5,949 9,915 11,237 29,745 33,711 56,185 101,133 168,555 and 505,665, with no remainder.
Since 505,665 cannot be divided by just 1 and 505,665, it is not a prime number.