The number 1,233,540 can be evenly divided by 1 2 3 4 5 6 7 9 10 11 12 14 15 18 20 21 22 28 30 33 35 36 42 44 45 55 60 63 66 70 77 84 89 90 99 105 110 126 132 140 154 165 178 180 198 210 220 231 252 267 308 315 330 356 385 396 420 445 462 495 534 623 630 660 693 770 801 890 924 979 990 1,068 1,155 1,246 1,260 1,335 1,386 1,540 1,602 1,780 1,869 1,958 1,980 2,310 2,492 2,670 2,772 2,937 3,115 3,204 3,465 3,738 3,916 4,005 4,620 4,895 5,340 5,607 5,874 6,230 6,853 6,930 7,476 8,010 8,811 9,345 9,790 11,214 11,748 12,460 13,706 13,860 14,685 16,020 17,622 18,690 19,580 20,559 22,428 27,412 28,035 29,370 34,265 35,244 37,380 41,118 44,055 56,070 58,740 61,677 68,530 82,236 88,110 102,795 112,140 123,354 137,060 176,220 205,590 246,708 308,385 411,180 616,770 and 1,233,540, with no remainder.
Since 1,233,540 cannot be divided by just 1 and 1,233,540, it is a composite number.