A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4084080 can be evenly divided by 1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 20 21 22 24 26 28 30 33 34 35 39 40 42 44 48 51 52 55 56 60 65 66 68 70 77 78 80 84 85 88 91 102 104 105 110 112 119 120 130 132 136 140 143 154 156 165 168 170 176 182 187 195 204 208 210 220 221 231 238 240 255 260 264 272 273 280 286 308 312 330 336 340 357 364 374 385 390 408 420 429 440 442 455 462 476 510 520 528 546 560 561 572 595 616 624 660 663 680 714 715 728 748 770 780 816 840 858 880 884 910 924 935 952 1,001 1,020 1,040 1,092 1,105 1,122 1,144 1,155 1,190 1,232 1,309 1,320 1,326 1,360 1,365 1,428 1,430 1,456 1,496 1,540 1,547 1,560 1,680 1,716 1,768 1,785 1,820 1,848 1,870 1,904 2,002 2,040 2,145 2,184 2,210 2,244 2,288 2,310 2,380 2,431 2,618 2,640 2,652 2,730 2,805 2,856 2,860 2,992 3,003 3,080 3,094 3,120 3,315 3,432 3,536 3,570 3,640 3,696 3,740 3,927 4,004 4,080 4,290 4,368 4,420 4,488 4,620 4,641 4,760 4,862 5,005 5,236 5,304 5,460 5,610 5,712 5,720 6,006 6,160 6,188 6,545 6,630 6,864 7,140 7,280 7,293 7,480 7,735 7,854 8,008 8,580 8,840 8,976 9,240 9,282 9,520 9,724 10,010 10,472 10,608 10,920 11,220 11,440 12,012 12,155 12,376 13,090 13,260 14,280 14,586 14,960 15,015 15,470 15,708 16,016 17,017 17,160 17,680 18,480 18,564 19,448 19,635 20,020 20,944 21,840 22,440 23,205 24,024 24,310 24,752 26,180 26,520 28,560 29,172 30,030 30,940 31,416 34,034 34,320 36,465 37,128 38,896 39,270 40,040 44,880 46,410 48,048 48,620 51,051 52,360 53,040 58,344 60,060 61,880 62,832 68,068 72,930 74,256 78,540 80,080 85,085 92,820 97,240 102,102 104,720 116,688 120,120 123,760 136,136 145,860 157,080 170,170 185,640 194,480 204,204 240,240 255,255 272,272 291,720 314,160 340,340 371,280 408,408 510,510 583,440 680,680 816,816 1,021,020 1,361,360 2,042,040 and 4,084,080, with no remainder.
Since 4,084,080 cannot be divided by just 1 and 4,084,080, it is not a prime number.