A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2337720 can be evenly divided by 1 2 3 4 5 6 7 8 10 11 12 14 15 20 21 22 23 24 28 30 33 35 40 42 44 46 55 56 60 66 69 70 77 84 88 92 105 110 115 120 121 132 138 140 154 161 165 168 184 210 220 230 231 242 253 264 276 280 308 322 330 345 363 385 420 440 460 462 483 484 506 552 605 616 644 660 690 726 759 770 805 840 847 920 924 966 968 1,012 1,155 1,210 1,265 1,288 1,320 1,380 1,452 1,518 1,540 1,610 1,694 1,771 1,815 1,848 1,932 2,024 2,310 2,415 2,420 2,530 2,541 2,760 2,783 2,904 3,036 3,080 3,220 3,388 3,542 3,630 3,795 3,864 4,235 4,620 4,830 4,840 5,060 5,082 5,313 5,566 6,072 6,440 6,776 7,084 7,260 7,590 8,349 8,470 8,855 9,240 9,660 10,120 10,164 10,626 11,132 12,705 13,915 14,168 14,520 15,180 16,698 16,940 17,710 19,320 19,481 20,328 21,252 22,264 25,410 26,565 27,830 30,360 33,396 33,880 35,420 38,962 41,745 42,504 50,820 53,130 55,660 58,443 66,792 70,840 77,924 83,490 97,405 101,640 106,260 111,320 116,886 155,848 166,980 194,810 212,520 233,772 292,215 333,960 389,620 467,544 584,430 779,240 1,168,860 and 2,337,720, with no remainder.
Since 2,337,720 cannot be divided by just 1 and 2,337,720, it is not a prime number.