Q: Is 686,420 a Prime Number?
A: No, 686,420 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 686420 can be evenly divided by 1 2 4 5 7 10 14 20 28 35 70 140 4,903 9,806 19,612 24,515 34,321 49,030 68,642 98,060 137,284 171,605 343,210 and 686,420, with no remainder.
Since 686,420 cannot be divided by just 1 and 686,420, it is not a prime number.