A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 844560 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 15 16 17 18 20 23 24 27 30 34 36 40 45 46 48 51 54 60 68 69 72 80 85 90 92 102 108 115 120 135 136 138 144 153 170 180 184 204 207 216 230 240 255 270 272 276 306 340 345 360 368 391 408 414 432 459 460 510 540 552 612 621 680 690 720 765 782 816 828 918 920 1,020 1,035 1,080 1,104 1,173 1,224 1,242 1,360 1,380 1,530 1,564 1,656 1,836 1,840 1,955 2,040 2,070 2,160 2,295 2,346 2,448 2,484 2,760 3,060 3,105 3,128 3,312 3,519 3,672 3,910 4,080 4,140 4,590 4,692 4,968 5,520 5,865 6,120 6,210 6,256 7,038 7,344 7,820 8,280 9,180 9,384 9,936 10,557 11,730 12,240 12,420 14,076 15,640 16,560 17,595 18,360 18,768 21,114 23,460 24,840 28,152 31,280 35,190 36,720 42,228 46,920 49,680 52,785 56,304 70,380 84,456 93,840 105,570 140,760 168,912 211,140 281,520 422,280 and 844,560, with no remainder.
Since 844,560 cannot be divided by just 1 and 844,560, it is not a prime number.