A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1048800 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 16 19 20 23 24 25 30 32 38 40 46 48 50 57 60 69 75 76 80 92 95 96 100 114 115 120 138 150 152 160 184 190 200 228 230 240 276 285 300 304 345 368 380 400 437 456 460 475 480 552 570 575 600 608 690 736 760 800 874 912 920 950 1,104 1,140 1,150 1,200 1,311 1,380 1,425 1,520 1,725 1,748 1,824 1,840 1,900 2,185 2,208 2,280 2,300 2,400 2,622 2,760 2,850 3,040 3,450 3,496 3,680 3,800 4,370 4,560 4,600 5,244 5,520 5,700 6,555 6,900 6,992 7,600 8,740 9,120 9,200 10,488 10,925 11,040 11,400 13,110 13,800 13,984 15,200 17,480 18,400 20,976 21,850 22,800 26,220 27,600 32,775 34,960 41,952 43,700 45,600 52,440 55,200 65,550 69,920 87,400 104,880 131,100 174,800 209,760 262,200 349,600 524,400 and 1,048,800, with no remainder.
Since 1,048,800 cannot be divided by just 1 and 1,048,800, it is not a prime number.