A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2868000 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 16 20 24 25 30 32 40 48 50 60 75 80 96 100 120 125 150 160 200 239 240 250 300 375 400 478 480 500 600 717 750 800 956 1,000 1,195 1,200 1,434 1,500 1,912 2,000 2,390 2,400 2,868 3,000 3,585 3,824 4,000 4,780 5,736 5,975 6,000 7,170 7,648 9,560 11,472 11,950 12,000 14,340 17,925 19,120 22,944 23,900 28,680 29,875 35,850 38,240 47,800 57,360 59,750 71,700 89,625 95,600 114,720 119,500 143,400 179,250 191,200 239,000 286,800 358,500 478,000 573,600 717,000 956,000 1,434,000 and 2,868,000, with no remainder.
Since 2,868,000 cannot be divided by just 1 and 2,868,000, it is not a prime number.