Q: Is 661,521 a Prime Number?
A: No, 661,521 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 661521 can be evenly divided by 1 3 7 17 21 51 109 119 289 327 357 763 867 1,853 2,023 2,289 5,559 6,069 12,971 31,501 38,913 94,503 220,507 and 661,521, with no remainder.
Since 661,521 cannot be divided by just 1 and 661,521, it is not a prime number.