A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2712160 can be evenly divided by 1 2 4 5 8 10 11 16 20 22 23 32 40 44 46 55 67 80 88 92 110 115 134 160 176 184 220 230 253 268 335 352 368 440 460 506 536 670 736 737 880 920 1,012 1,072 1,265 1,340 1,474 1,541 1,760 1,840 2,024 2,144 2,530 2,680 2,948 3,082 3,680 3,685 4,048 5,060 5,360 5,896 6,164 7,370 7,705 8,096 10,120 10,720 11,792 12,328 14,740 15,410 16,951 20,240 23,584 24,656 29,480 30,820 33,902 40,480 49,312 58,960 61,640 67,804 84,755 117,920 123,280 135,608 169,510 246,560 271,216 339,020 542,432 678,040 1,356,080 and 2,712,160, with no remainder.
Since 2,712,160 cannot be divided by just 1 and 2,712,160, it is not a prime number.