Q: Is 666,624 a Prime Number?
A: No, 666,624 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 666624 can be evenly divided by 1 2 3 4 6 7 8 12 14 16 21 24 28 31 32 42 48 56 62 64 84 93 96 112 124 128 168 186 192 217 224 248 256 336 372 384 434 448 496 512 651 672 744 768 868 896 992 1,024 1,302 1,344 1,488 1,536 1,736 1,792 1,984 2,604 2,688 2,976 3,072 3,472 3,584 3,968 5,208 5,376 5,952 6,944 7,168 7,936 10,416 10,752 11,904 13,888 15,872 20,832 21,504 23,808 27,776 31,744 41,664 47,616 55,552 83,328 95,232 111,104 166,656 222,208 333,312 and 666,624, with no remainder.
Since 666,624 cannot be divided by just 1 and 666,624, it is not a prime number.