A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5851230 can be evenly divided by 1 2 3 5 6 7 10 11 14 15 17 21 22 30 33 34 35 42 51 55 66 70 77 85 102 105 110 119 149 154 165 170 187 210 231 238 255 298 330 357 374 385 447 462 510 561 595 714 745 770 894 935 1,043 1,122 1,155 1,190 1,309 1,490 1,639 1,785 1,870 2,086 2,235 2,310 2,533 2,618 2,805 3,129 3,278 3,570 3,927 4,470 4,917 5,066 5,215 5,610 6,258 6,545 7,599 7,854 8,195 9,834 10,430 11,473 12,665 13,090 15,198 15,645 16,390 17,731 19,635 22,946 24,585 25,330 27,863 31,290 34,419 35,462 37,995 39,270 49,170 53,193 55,726 57,365 68,838 75,990 83,589 88,655 106,386 114,730 139,315 167,178 172,095 177,310 195,041 265,965 278,630 344,190 390,082 417,945 531,930 585,123 835,890 975,205 1,170,246 1,950,410 2,925,615 and 5,851,230, with no remainder.
Since 5,851,230 cannot be divided by just 1 and 5,851,230, it is not a prime number.