A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2676960 can be evenly divided by 1 2 3 4 5 6 8 9 10 11 12 13 15 16 18 20 22 24 26 30 32 33 36 39 40 44 45 48 52 55 60 65 66 72 78 80 88 90 96 99 104 110 117 120 130 132 143 144 156 160 165 169 176 180 195 198 208 220 234 240 260 264 286 288 312 330 338 352 360 390 396 416 429 440 468 480 495 507 520 528 572 585 624 660 676 715 720 780 792 845 858 880 936 990 1,014 1,040 1,056 1,144 1,170 1,248 1,287 1,320 1,352 1,430 1,440 1,521 1,560 1,584 1,690 1,716 1,760 1,859 1,872 1,980 2,028 2,080 2,145 2,288 2,340 2,535 2,574 2,640 2,704 2,860 3,042 3,120 3,168 3,380 3,432 3,718 3,744 3,960 4,056 4,290 4,576 4,680 5,070 5,148 5,280 5,408 5,577 5,720 6,084 6,240 6,435 6,760 6,864 7,436 7,605 7,920 8,112 8,580 9,295 9,360 10,140 10,296 11,154 11,440 12,168 12,870 13,520 13,728 14,872 15,210 15,840 16,224 16,731 17,160 18,590 18,720 20,280 20,592 22,308 22,880 24,336 25,740 27,040 27,885 29,744 30,420 33,462 34,320 37,180 40,560 41,184 44,616 48,672 51,480 55,770 59,488 60,840 66,924 68,640 74,360 81,120 83,655 89,232 102,960 111,540 121,680 133,848 148,720 167,310 178,464 205,920 223,080 243,360 267,696 297,440 334,620 446,160 535,392 669,240 892,320 1,338,480 and 2,676,960, with no remainder.
Since 2,676,960 cannot be divided by just 1 and 2,676,960, it is not a prime number.