A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5758872 can be evenly divided by 1 2 3 4 6 7 8 12 14 21 24 28 42 49 56 59 83 84 98 118 147 166 168 177 196 236 249 294 332 354 392 413 472 498 581 588 664 708 826 996 1,162 1,176 1,239 1,416 1,652 1,743 1,992 2,324 2,478 2,891 3,304 3,486 4,067 4,648 4,897 4,956 5,782 6,972 8,134 8,673 9,794 9,912 11,564 12,201 13,944 14,691 16,268 17,346 19,588 23,128 24,402 29,382 32,536 34,279 34,692 39,176 48,804 58,764 68,558 69,384 97,608 102,837 117,528 137,116 205,674 239,953 274,232 411,348 479,906 719,859 822,696 959,812 1,439,718 1,919,624 2,879,436 and 5,758,872, with no remainder.
Since 5,758,872 cannot be divided by just 1 and 5,758,872, it is not a prime number.