The number 3,188,808 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 18 19 21 24 27 28 36 37 38 42 54 56 57 63 72 74 76 81 84 108 111 114 126 133 148 152 162 168 171 189 216 222 228 252 259 266 296 324 333 342 378 399 444 456 504 513 518 532 567 648 666 684 703 756 777 798 888 999 1,026 1,036 1,064 1,134 1,197 1,332 1,368 1,406 1,512 1,539 1,554 1,596 1,998 2,052 2,072 2,109 2,268 2,331 2,394 2,664 2,812 2,997 3,078 3,108 3,192 3,591 3,996 4,104 4,218 4,536 4,662 4,788 4,921 5,624 5,994 6,156 6,216 6,327 6,993 7,182 7,992 8,436 9,324 9,576 9,842 10,773 11,988 12,312 12,654 13,986 14,364 14,763 16,872 18,648 18,981 19,684 20,979 21,546 23,976 25,308 27,972 28,728 29,526 37,962 39,368 41,958 43,092 44,289 50,616 55,944 56,943 59,052 75,924 83,916 86,184 88,578 113,886 118,104 132,867 151,848 167,832 177,156 227,772 265,734 354,312 398,601 455,544 531,468 797,202 1,062,936 1,594,404 and 3,188,808, with no remainder.
Since 3,188,808 cannot be divided by just 1 and 3,188,808, it is a composite number.