A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 8307900 can be evenly divided by 1 2 3 4 5 6 9 10 12 15 17 18 20 25 27 30 34 36 45 50 51 54 60 68 75 85 90 100 102 108 135 150 153 170 180 181 204 225 255 270 300 306 340 362 425 450 459 510 540 543 612 675 724 765 850 900 905 918 1,020 1,086 1,275 1,350 1,530 1,629 1,700 1,810 1,836 2,172 2,295 2,550 2,700 2,715 3,060 3,077 3,258 3,620 3,825 4,525 4,590 4,887 5,100 5,430 6,154 6,516 7,650 8,145 9,050 9,180 9,231 9,774 10,860 11,475 12,308 13,575 15,300 15,385 16,290 18,100 18,462 19,548 22,950 24,435 27,150 27,693 30,770 32,580 36,924 40,725 45,900 46,155 48,870 54,300 55,386 61,540 76,925 81,450 83,079 92,310 97,740 110,772 122,175 138,465 153,850 162,900 166,158 184,620 230,775 244,350 276,930 307,700 332,316 415,395 461,550 488,700 553,860 692,325 830,790 923,100 1,384,650 1,661,580 2,076,975 2,769,300 4,153,950 and 8,307,900, with no remainder.
Since 8,307,900 cannot be divided by just 1 and 8,307,900, it is not a prime number.