A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3000480 can be evenly divided by 1 2 3 4 5 6 7 8 10 12 14 15 16 19 20 21 24 28 30 32 35 38 40 42 47 48 56 57 60 70 76 80 84 94 95 96 105 112 114 120 133 140 141 152 160 168 188 190 210 224 228 235 240 266 280 282 285 304 329 336 376 380 399 420 456 470 480 532 560 564 570 608 658 665 672 705 752 760 798 840 893 912 940 987 1,064 1,120 1,128 1,140 1,316 1,330 1,410 1,504 1,520 1,596 1,645 1,680 1,786 1,824 1,880 1,974 1,995 2,128 2,256 2,280 2,632 2,660 2,679 2,820 3,040 3,192 3,290 3,360 3,572 3,760 3,948 3,990 4,256 4,465 4,512 4,560 4,935 5,264 5,320 5,358 5,640 6,251 6,384 6,580 7,144 7,520 7,896 7,980 8,930 9,120 9,870 10,528 10,640 10,716 11,280 12,502 12,768 13,160 13,395 14,288 15,792 15,960 17,860 18,753 19,740 21,280 21,432 22,560 25,004 26,320 26,790 28,576 31,255 31,584 31,920 35,720 37,506 39,480 42,864 50,008 52,640 53,580 62,510 63,840 71,440 75,012 78,960 85,728 93,765 100,016 107,160 125,020 142,880 150,024 157,920 187,530 200,032 214,320 250,040 300,048 375,060 428,640 500,080 600,096 750,120 1,000,160 1,500,240 and 3,000,480, with no remainder.
Since 3,000,480 cannot be divided by just 1 and 3,000,480, it is not a prime number.