The number 1,908,816 can be evenly divided by 1 2 3 4 6 7 8 12 13 14 16 19 21 23 24 26 28 38 39 42 46 48 52 56 57 69 76 78 84 91 92 104 112 114 133 138 152 156 161 168 182 184 208 228 247 266 273 276 299 304 312 322 336 364 368 399 437 456 483 494 532 546 552 598 624 644 728 741 798 874 897 912 966 988 1,064 1,092 1,104 1,196 1,288 1,311 1,456 1,482 1,596 1,729 1,748 1,794 1,932 1,976 2,093 2,128 2,184 2,392 2,576 2,622 2,964 3,059 3,192 3,458 3,496 3,588 3,864 3,952 4,186 4,368 4,784 5,187 5,244 5,681 5,928 6,118 6,279 6,384 6,916 6,992 7,176 7,728 8,372 9,177 10,374 10,488 11,362 11,856 12,236 12,558 13,832 14,352 16,744 17,043 18,354 20,748 20,976 22,724 24,472 25,116 27,664 33,488 34,086 36,708 39,767 41,496 45,448 48,944 50,232 68,172 73,416 79,534 82,992 90,896 100,464 119,301 136,344 146,832 159,068 238,602 272,688 318,136 477,204 636,272 954,408 and 1,908,816, with no remainder.
Since 1,908,816 cannot be divided by just 1 and 1,908,816, it is a composite number.