The number 3,651,600 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 16 17 20 24 25 30 34 40 48 50 51 60 68 75 80 85 100 102 120 136 150 170 179 200 204 240 255 272 300 340 358 400 408 425 510 537 600 680 716 816 850 895 1,020 1,074 1,200 1,275 1,360 1,432 1,700 1,790 2,040 2,148 2,550 2,685 2,864 3,043 3,400 3,580 4,080 4,296 4,475 5,100 5,370 6,086 6,800 7,160 8,592 8,950 9,129 10,200 10,740 12,172 13,425 14,320 15,215 17,900 18,258 20,400 21,480 24,344 26,850 30,430 35,800 36,516 42,960 45,645 48,688 53,700 60,860 71,600 73,032 76,075 91,290 107,400 121,720 146,064 152,150 182,580 214,800 228,225 243,440 304,300 365,160 456,450 608,600 730,320 912,900 1,217,200 1,825,800 and 3,651,600, with no remainder.
Since 3,651,600 cannot be divided by just 1 and 3,651,600, it is a composite number.