A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 980280 can be evenly divided by 1 2 3 4 5 6 7 8 9 10 12 14 15 18 20 21 24 28 30 35 36 40 42 45 56 60 63 70 72 84 90 105 120 126 140 168 180 210 252 280 315 360 389 420 504 630 778 840 1,167 1,260 1,556 1,945 2,334 2,520 2,723 3,112 3,501 3,890 4,668 5,446 5,835 7,002 7,780 8,169 9,336 10,892 11,670 13,615 14,004 15,560 16,338 17,505 21,784 23,340 24,507 27,230 28,008 32,676 35,010 40,845 46,680 49,014 54,460 65,352 70,020 81,690 98,028 108,920 122,535 140,040 163,380 196,056 245,070 326,760 490,140 and 980,280, with no remainder.
Since 980,280 cannot be divided by just 1 and 980,280, it is not a prime number.