The number 6,231,456 can be evenly divided by 1 2 3 4 6 7 8 9 11 12 14 16 18 21 22 24 28 32 33 36 42 44 48 56 63 66 72 77 84 88 96 99 112 126 132 144 154 168 176 198 224 231 252 264 281 288 308 336 352 396 462 504 528 562 616 672 693 792 843 924 1,008 1,056 1,124 1,232 1,386 1,584 1,686 1,848 1,967 2,016 2,248 2,464 2,529 2,772 3,091 3,168 3,372 3,696 3,934 4,496 5,058 5,544 5,901 6,182 6,744 7,392 7,868 8,992 9,273 10,116 11,088 11,802 12,364 13,488 15,736 17,703 18,546 20,232 21,637 22,176 23,604 24,728 26,976 27,819 31,472 35,406 37,092 40,464 43,274 47,208 49,456 55,638 62,944 64,911 70,812 74,184 80,928 86,548 94,416 98,912 111,276 129,822 141,624 148,368 173,096 188,832 194,733 222,552 259,644 283,248 296,736 346,192 389,466 445,104 519,288 566,496 692,384 778,932 890,208 1,038,576 1,557,864 2,077,152 3,115,728 and 6,231,456, with no remainder.
Since 6,231,456 cannot be divided by just 1 and 6,231,456, it is a composite number.