The number 6,649,380 can be evenly divided by 1 2 3 4 5 6 9 10 12 15 17 18 20 30 34 36 41 45 51 53 60 68 82 85 90 102 106 123 153 159 164 170 180 204 205 212 246 255 265 306 318 340 369 410 477 492 510 530 612 615 636 697 738 765 795 820 901 954 1,020 1,060 1,230 1,394 1,476 1,530 1,590 1,802 1,845 1,908 2,091 2,173 2,385 2,460 2,703 2,788 3,060 3,180 3,485 3,604 3,690 4,182 4,346 4,505 4,770 5,406 6,273 6,519 6,970 7,380 8,109 8,364 8,692 9,010 9,540 10,455 10,812 10,865 12,546 13,038 13,515 13,940 16,218 18,020 19,557 20,910 21,730 25,092 26,076 27,030 31,365 32,436 32,595 36,941 39,114 40,545 41,820 43,460 54,060 62,730 65,190 73,882 78,228 81,090 97,785 110,823 125,460 130,380 147,764 162,180 184,705 195,570 221,646 332,469 369,410 391,140 443,292 554,115 664,938 738,820 1,108,230 1,329,876 1,662,345 2,216,460 3,324,690 and 6,649,380, with no remainder.
Since 6,649,380 cannot be divided by just 1 and 6,649,380, it is a composite number.