Q: Is 521,561 a Prime Number?
A: No, 521,561 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 521561 can be evenly divided by 1 41 12,721 and 521,561, with no remainder.
Since 521,561 cannot be divided by just 1 and 521,561, it is not a prime number.