The number 2,001,600 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 15 16 18 20 24 25 30 32 36 40 45 48 50 60 64 72 75 80 90 96 100 120 139 144 150 160 180 192 200 225 240 278 288 300 320 360 400 417 450 480 556 576 600 695 720 800 834 900 960 1,112 1,200 1,251 1,390 1,440 1,600 1,668 1,800 2,085 2,224 2,400 2,502 2,780 2,880 3,336 3,475 3,600 4,170 4,448 4,800 5,004 5,560 6,255 6,672 6,950 7,200 8,340 8,896 10,008 10,425 11,120 12,510 13,344 13,900 14,400 16,680 20,016 20,850 22,240 25,020 26,688 27,800 31,275 33,360 40,032 41,700 44,480 50,040 55,600 62,550 66,720 80,064 83,400 100,080 111,200 125,100 133,440 166,800 200,160 222,400 250,200 333,600 400,320 500,400 667,200 1,000,800 and 2,001,600, with no remainder.
Since 2,001,600 cannot be divided by just 1 and 2,001,600, it is a composite number.