A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4176960 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 16 19 20 24 30 32 38 40 48 57 60 64 76 80 95 96 114 120 152 160 190 192 228 229 240 285 304 320 380 456 458 480 570 608 687 760 912 916 960 1,140 1,145 1,216 1,374 1,520 1,824 1,832 2,280 2,290 2,748 3,040 3,435 3,648 3,664 4,351 4,560 4,580 5,496 6,080 6,870 7,328 8,702 9,120 9,160 10,992 13,053 13,740 14,656 17,404 18,240 18,320 21,755 21,984 26,106 27,480 34,808 36,640 43,510 43,968 52,212 54,960 65,265 69,616 73,280 87,020 104,424 109,920 130,530 139,232 174,040 208,848 219,840 261,060 278,464 348,080 417,696 522,120 696,160 835,392 1,044,240 1,392,320 2,088,480 and 4,176,960, with no remainder.
Since 4,176,960 cannot be divided by just 1 and 4,176,960, it is not a prime number.