A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 6250050 can be evenly divided by 1 2 3 5 6 9 10 15 17 18 19 25 30 34 38 43 45 50 51 57 75 85 86 90 95 102 114 129 150 153 170 171 190 215 225 255 258 285 306 323 342 387 425 430 450 475 510 570 645 646 731 765 774 817 850 855 950 969 1,075 1,275 1,290 1,425 1,462 1,530 1,615 1,634 1,710 1,935 1,938 2,150 2,193 2,451 2,550 2,850 2,907 3,225 3,230 3,655 3,825 3,870 4,085 4,275 4,386 4,845 4,902 5,814 6,450 6,579 7,310 7,353 7,650 8,075 8,170 8,550 9,675 9,690 10,965 12,255 13,158 13,889 14,535 14,706 16,150 18,275 19,350 20,425 21,930 24,225 24,510 27,778 29,070 32,895 36,550 36,765 40,850 41,667 48,450 54,825 61,275 65,790 69,445 72,675 73,530 83,334 109,650 122,550 125,001 138,890 145,350 164,475 183,825 208,335 250,002 328,950 347,225 367,650 416,670 625,005 694,450 1,041,675 1,250,010 2,083,350 3,125,025 and 6,250,050, with no remainder.
Since 6,250,050 cannot be divided by just 1 and 6,250,050, it is not a prime number.