The number 1,291,248 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 16 18 21 24 27 28 36 42 48 49 54 56 61 63 72 84 98 108 112 122 126 144 147 168 183 189 196 216 244 252 294 336 366 378 392 427 432 441 488 504 549 588 732 756 784 854 882 976 1,008 1,098 1,176 1,281 1,323 1,464 1,512 1,647 1,708 1,764 2,196 2,352 2,562 2,646 2,928 2,989 3,024 3,294 3,416 3,528 3,843 4,392 5,124 5,292 5,978 6,588 6,832 7,056 7,686 8,784 8,967 10,248 10,584 11,529 11,956 13,176 15,372 17,934 20,496 21,168 23,058 23,912 26,352 26,901 30,744 35,868 46,116 47,824 53,802 61,488 71,736 80,703 92,232 107,604 143,472 161,406 184,464 215,208 322,812 430,416 645,624 and 1,291,248, with no remainder.
Since 1,291,248 cannot be divided by just 1 and 1,291,248, it is a composite number.