A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7994250 can be evenly divided by 1 2 3 5 6 9 10 11 15 17 18 19 22 25 30 33 34 38 45 50 51 55 57 66 75 85 90 95 99 102 110 114 125 150 153 165 170 171 187 190 198 209 225 250 255 275 285 306 323 330 342 374 375 418 425 450 475 495 510 550 561 570 627 646 750 765 825 850 855 935 950 969 990 1,045 1,122 1,125 1,254 1,275 1,375 1,425 1,530 1,615 1,650 1,683 1,710 1,870 1,881 1,938 2,090 2,125 2,250 2,375 2,475 2,550 2,750 2,805 2,850 2,907 3,135 3,230 3,366 3,553 3,762 3,825 4,125 4,250 4,275 4,675 4,750 4,845 4,950 5,225 5,610 5,814 6,270 6,375 7,106 7,125 7,650 8,075 8,250 8,415 8,550 9,350 9,405 9,690 10,450 10,659 12,375 12,750 14,025 14,250 14,535 15,675 16,150 16,830 17,765 18,810 19,125 21,318 21,375 23,375 24,225 24,750 26,125 28,050 29,070 31,350 31,977 35,530 38,250 40,375 42,075 42,750 46,750 47,025 48,450 52,250 53,295 63,954 70,125 72,675 78,375 80,750 84,150 88,825 94,050 106,590 121,125 140,250 145,350 156,750 159,885 177,650 210,375 235,125 242,250 266,475 319,770 363,375 420,750 444,125 470,250 532,950 726,750 799,425 888,250 1,332,375 1,598,850 2,664,750 3,997,125 and 7,994,250, with no remainder.
Since 7,994,250 cannot be divided by just 1 and 7,994,250, it is not a prime number.