A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5100810 can be evenly divided by 1 2 3 5 6 10 11 13 15 22 26 29 30 33 39 41 55 58 65 66 78 82 87 110 123 130 143 145 165 174 195 205 246 286 290 319 330 377 390 410 429 435 451 533 615 638 715 754 858 870 902 957 1,066 1,131 1,189 1,230 1,353 1,430 1,595 1,599 1,885 1,914 2,145 2,255 2,262 2,378 2,665 2,706 3,190 3,198 3,567 3,770 4,147 4,290 4,510 4,785 5,330 5,655 5,863 5,945 6,765 7,134 7,995 8,294 9,570 11,310 11,726 11,890 12,441 13,079 13,530 15,457 15,990 17,589 17,835 20,735 24,882 26,158 29,315 30,914 35,178 35,670 39,237 41,470 46,371 58,630 62,205 65,395 77,285 78,474 87,945 92,742 124,410 130,790 154,570 170,027 175,890 196,185 231,855 340,054 392,370 463,710 510,081 850,135 1,020,162 1,700,270 2,550,405 and 5,100,810, with no remainder.
Since 5,100,810 cannot be divided by just 1 and 5,100,810, it is not a prime number.