Q: Is 321,640 a Prime Number?
A: No, 321,640 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 321640 can be evenly divided by 1 2 4 5 8 10 11 17 20 22 34 40 43 44 55 68 85 86 88 110 136 170 172 187 215 220 340 344 374 430 440 473 680 731 748 860 935 946 1,462 1,496 1,720 1,870 1,892 2,365 2,924 3,655 3,740 3,784 4,730 5,848 7,310 7,480 8,041 9,460 14,620 16,082 18,920 29,240 32,164 40,205 64,328 80,410 160,820 and 321,640, with no remainder.
Since 321,640 cannot be divided by just 1 and 321,640, it is not a prime number.