The number 6,344,400 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 85 100 102 120 136 150 170 200 204 240 255 272 300 311 340 400 408 425 510 600 622 680 816 850 933 1,020 1,200 1,244 1,275 1,360 1,555 1,700 1,866 2,040 2,488 2,550 3,110 3,400 3,732 4,080 4,665 4,976 5,100 5,287 6,220 6,800 7,464 7,775 9,330 10,200 10,574 12,440 14,928 15,550 15,861 18,660 20,400 21,148 23,325 24,880 26,435 31,100 31,722 37,320 42,296 46,650 52,870 62,200 63,444 74,640 79,305 84,592 93,300 105,740 124,400 126,888 132,175 158,610 186,600 211,480 253,776 264,350 317,220 373,200 396,525 422,960 528,700 634,440 793,050 1,057,400 1,268,880 1,586,100 2,114,800 3,172,200 and 6,344,400, with no remainder.
Since 6,344,400 cannot be divided by just 1 and 6,344,400, it is a composite number.