A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1420200 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 15 18 20 24 25 27 30 36 40 45 50 54 60 72 75 90 100 108 120 135 150 180 200 216 225 263 270 300 360 450 526 540 600 675 789 900 1,052 1,080 1,315 1,350 1,578 1,800 2,104 2,367 2,630 2,700 3,156 3,945 4,734 5,260 5,400 6,312 6,575 7,101 7,890 9,468 10,520 11,835 13,150 14,202 15,780 18,936 19,725 23,670 26,300 28,404 31,560 35,505 39,450 47,340 52,600 56,808 59,175 71,010 78,900 94,680 118,350 142,020 157,800 177,525 236,700 284,040 355,050 473,400 710,100 and 1,420,200, with no remainder.
Since 1,420,200 cannot be divided by just 1 and 1,420,200, it is not a prime number.