A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7956960 can be evenly divided by 1 2 3 4 5 6 8 10 11 12 15 16 20 22 24 30 32 33 40 44 48 55 60 66 80 88 96 110 120 121 132 137 160 165 176 220 240 242 264 274 330 352 363 411 440 480 484 528 548 605 660 685 726 822 880 968 1,056 1,096 1,210 1,320 1,370 1,452 1,507 1,644 1,760 1,815 1,936 2,055 2,192 2,420 2,640 2,740 2,904 3,014 3,288 3,630 3,872 4,110 4,384 4,521 4,840 5,280 5,480 5,808 6,028 6,576 7,260 7,535 8,220 9,042 9,680 10,960 11,616 12,056 13,152 14,520 15,070 16,440 16,577 18,084 19,360 21,920 22,605 24,112 29,040 30,140 32,880 33,154 36,168 45,210 48,224 49,731 58,080 60,280 65,760 66,308 72,336 82,885 90,420 99,462 120,560 132,616 144,672 165,770 180,840 198,924 241,120 248,655 265,232 331,540 361,680 397,848 497,310 530,464 663,080 723,360 795,696 994,620 1,326,160 1,591,392 1,989,240 2,652,320 3,978,480 and 7,956,960, with no remainder.
Since 7,956,960 cannot be divided by just 1 and 7,956,960, it is not a prime number.