Q: Is 666,840 a Prime Number?
A: No, 666,840 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 666840 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 20 24 30 40 60 120 5,557 11,114 16,671 22,228 27,785 33,342 44,456 55,570 66,684 83,355 111,140 133,368 166,710 222,280 333,420 and 666,840, with no remainder.
Since 666,840 cannot be divided by just 1 and 666,840, it is not a prime number.