A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1012000 can be evenly divided by 1 2 4 5 8 10 11 16 20 22 23 25 32 40 44 46 50 55 80 88 92 100 110 115 125 160 176 184 200 220 230 250 253 275 352 368 400 440 460 500 506 550 575 736 800 880 920 1,000 1,012 1,100 1,150 1,265 1,375 1,760 1,840 2,000 2,024 2,200 2,300 2,530 2,750 2,875 3,680 4,000 4,048 4,400 4,600 5,060 5,500 5,750 6,325 8,096 8,800 9,200 10,120 11,000 11,500 12,650 18,400 20,240 22,000 23,000 25,300 31,625 40,480 44,000 46,000 50,600 63,250 92,000 101,200 126,500 202,400 253,000 506,000 and 1,012,000, with no remainder.
Since 1,012,000 cannot be divided by just 1 and 1,012,000, it is not a prime number.