Q: Is 521,720 a Prime Number?
A: No, 521,720 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 521720 can be evenly divided by 1 2 4 5 8 10 20 40 13,043 26,086 52,172 65,215 104,344 130,430 260,860 and 521,720, with no remainder.
Since 521,720 cannot be divided by just 1 and 521,720, it is not a prime number.