A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1477080 can be evenly divided by 1 2 3 4 5 6 8 9 10 11 12 15 18 20 22 24 30 33 36 40 44 45 55 60 66 72 88 90 99 110 120 132 165 180 198 220 264 330 360 373 396 440 495 660 746 792 990 1,119 1,320 1,492 1,865 1,980 2,238 2,984 3,357 3,730 3,960 4,103 4,476 5,595 6,714 7,460 8,206 8,952 11,190 12,309 13,428 14,920 16,412 16,785 20,515 22,380 24,618 26,856 32,824 33,570 36,927 41,030 44,760 49,236 61,545 67,140 73,854 82,060 98,472 123,090 134,280 147,708 164,120 184,635 246,180 295,416 369,270 492,360 738,540 and 1,477,080, with no remainder.
Since 1,477,080 cannot be divided by just 1 and 1,477,080, it is not a prime number.