The number 2,806,020 can be evenly divided by 1 2 3 4 5 6 7 9 10 12 14 15 17 18 20 21 28 30 34 35 36 42 45 51 60 63 68 70 84 85 90 102 105 119 126 131 140 153 170 180 204 210 238 252 255 262 306 315 340 357 393 420 476 510 524 595 612 630 655 714 765 786 917 1,020 1,071 1,179 1,190 1,260 1,310 1,428 1,530 1,572 1,785 1,834 1,965 2,142 2,227 2,358 2,380 2,620 2,751 3,060 3,570 3,668 3,930 4,284 4,454 4,585 4,716 5,355 5,502 5,895 6,681 7,140 7,860 8,253 8,908 9,170 10,710 11,004 11,135 11,790 13,362 13,755 15,589 16,506 18,340 20,043 21,420 22,270 23,580 26,724 27,510 31,178 33,012 33,405 40,086 41,265 44,540 46,767 55,020 62,356 66,810 77,945 80,172 82,530 93,534 100,215 133,620 140,301 155,890 165,060 187,068 200,430 233,835 280,602 311,780 400,860 467,670 561,204 701,505 935,340 1,403,010 and 2,806,020, with no remainder.
Since 2,806,020 cannot be divided by just 1 and 2,806,020, it is a composite number.