The number 3,400,320 can be evenly divided by 1 2 3 4 5 6 7 8 10 11 12 14 15 16 20 21 22 23 24 28 30 32 33 35 40 42 44 46 48 55 56 60 64 66 69 70 77 80 84 88 92 96 105 110 112 115 120 128 132 138 140 154 160 161 165 168 176 184 192 210 220 224 230 231 240 253 264 276 280 308 320 322 330 336 345 352 368 384 385 420 440 448 460 462 480 483 506 528 552 560 616 640 644 660 672 690 704 736 759 770 805 840 880 896 920 924 960 966 1,012 1,056 1,104 1,120 1,155 1,232 1,265 1,288 1,320 1,344 1,380 1,408 1,472 1,518 1,540 1,610 1,680 1,760 1,771 1,840 1,848 1,920 1,932 2,024 2,112 2,208 2,240 2,310 2,415 2,464 2,530 2,576 2,640 2,688 2,760 2,944 3,036 3,080 3,220 3,360 3,520 3,542 3,680 3,696 3,795 3,864 4,048 4,224 4,416 4,480 4,620 4,830 4,928 5,060 5,152 5,280 5,313 5,520 6,072 6,160 6,440 6,720 7,040 7,084 7,360 7,392 7,590 7,728 8,096 8,832 8,855 9,240 9,660 9,856 10,120 10,304 10,560 10,626 11,040 12,144 12,320 12,880 13,440 14,168 14,720 14,784 15,180 15,456 16,192 17,710 18,480 19,320 20,240 20,608 21,120 21,252 22,080 24,288 24,640 25,760 26,565 28,336 29,568 30,360 30,912 32,384 35,420 36,960 38,640 40,480 42,504 44,160 48,576 49,280 51,520 53,130 56,672 60,720 61,824 70,840 73,920 77,280 80,960 85,008 97,152 103,040 106,260 113,344 121,440 141,680 147,840 154,560 161,920 170,016 212,520 226,688 242,880 283,360 309,120 340,032 425,040 485,760 566,720 680,064 850,080 1,133,440 1,700,160 and 3,400,320, with no remainder.
Since 3,400,320 cannot be divided by just 1 and 3,400,320, it is a composite number.