A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 507600 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 15 16 18 20 24 25 27 30 36 40 45 47 48 50 54 60 72 75 80 90 94 100 108 120 135 141 144 150 180 188 200 216 225 235 240 270 282 300 360 376 400 423 432 450 470 540 564 600 675 705 720 752 846 900 940 1,080 1,128 1,175 1,200 1,269 1,350 1,410 1,692 1,800 1,880 2,115 2,160 2,256 2,350 2,538 2,700 2,820 3,384 3,525 3,600 3,760 4,230 4,700 5,076 5,400 5,640 6,345 6,768 7,050 8,460 9,400 10,152 10,575 10,800 11,280 12,690 14,100 16,920 18,800 20,304 21,150 25,380 28,200 31,725 33,840 42,300 50,760 56,400 63,450 84,600 101,520 126,900 169,200 253,800 and 507,600, with no remainder.
Since 507,600 cannot be divided by just 1 and 507,600, it is not a prime number.