Q: Is 521,220 a Prime Number?
A: No, 521,220 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 521220 can be evenly divided by 1 2 3 4 5 6 7 10 12 14 15 17 20 21 28 30 34 35 42 51 60 68 70 73 84 85 102 105 119 140 146 170 204 210 219 238 255 292 340 357 365 420 438 476 510 511 595 714 730 876 1,020 1,022 1,095 1,190 1,241 1,428 1,460 1,533 1,785 2,044 2,190 2,380 2,482 2,555 3,066 3,570 3,723 4,380 4,964 5,110 6,132 6,205 7,140 7,446 7,665 8,687 10,220 12,410 14,892 15,330 17,374 18,615 24,820 26,061 30,660 34,748 37,230 43,435 52,122 74,460 86,870 104,244 130,305 173,740 260,610 and 521,220, with no remainder.
Since 521,220 cannot be divided by just 1 and 521,220, it is not a prime number.