The number 4,257,990 can be evenly divided by 1 2 3 5 6 9 10 11 15 17 18 22 23 30 33 34 45 46 51 55 66 69 85 90 99 102 110 115 121 138 153 165 170 187 198 207 230 242 253 255 306 330 345 363 374 391 414 495 506 510 561 605 690 726 759 765 782 935 990 1,035 1,089 1,122 1,173 1,210 1,265 1,518 1,530 1,683 1,815 1,870 1,955 2,057 2,070 2,178 2,277 2,346 2,530 2,783 2,805 3,366 3,519 3,630 3,795 3,910 4,114 4,301 4,554 5,445 5,566 5,610 5,865 6,171 7,038 7,590 8,349 8,415 8,602 10,285 10,890 11,385 11,730 12,342 12,903 13,915 16,698 16,830 17,595 18,513 20,570 21,505 22,770 25,047 25,806 27,830 30,855 35,190 37,026 38,709 41,745 43,010 47,311 50,094 61,710 64,515 77,418 83,490 92,565 94,622 125,235 129,030 141,933 185,130 193,545 236,555 250,470 283,866 387,090 425,799 473,110 709,665 851,598 1,419,330 2,128,995 and 4,257,990, with no remainder.
Since 4,257,990 cannot be divided by just 1 and 4,257,990, it is a composite number.