A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1413720 can be evenly divided by 1 2 3 4 5 6 7 8 9 10 11 12 14 15 17 18 20 21 22 24 27 28 30 33 34 35 36 40 42 44 45 51 54 55 56 60 63 66 68 70 72 77 84 85 88 90 99 102 105 108 110 119 120 126 132 135 136 140 153 154 165 168 170 180 187 189 198 204 210 216 220 231 238 252 255 264 270 280 297 306 308 315 330 340 357 360 374 378 385 396 408 420 440 459 462 476 495 504 510 540 561 594 595 612 616 630 660 680 693 714 748 756 765 770 792 840 918 924 935 945 952 990 1,020 1,071 1,080 1,122 1,155 1,188 1,190 1,224 1,260 1,309 1,320 1,386 1,428 1,485 1,496 1,512 1,530 1,540 1,683 1,785 1,836 1,848 1,870 1,890 1,980 2,040 2,079 2,142 2,244 2,295 2,310 2,376 2,380 2,520 2,618 2,772 2,805 2,856 2,970 3,060 3,080 3,213 3,366 3,465 3,570 3,672 3,740 3,780 3,927 3,960 4,158 4,284 4,488 4,590 4,620 4,760 5,049 5,236 5,355 5,544 5,610 5,940 6,120 6,426 6,545 6,732 6,930 7,140 7,480 7,560 7,854 8,316 8,415 8,568 9,180 9,240 10,098 10,395 10,472 10,710 11,220 11,781 11,880 12,852 13,090 13,464 13,860 14,280 15,708 16,065 16,632 16,830 18,360 19,635 20,196 20,790 21,420 22,440 23,562 25,245 25,704 26,180 27,720 31,416 32,130 33,660 35,343 39,270 40,392 41,580 42,840 47,124 50,490 52,360 58,905 64,260 67,320 70,686 78,540 83,160 94,248 100,980 117,810 128,520 141,372 157,080 176,715 201,960 235,620 282,744 353,430 471,240 706,860 and 1,413,720, with no remainder.
Since 1,413,720 cannot be divided by just 1 and 1,413,720, it is not a prime number.