A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5190300 can be evenly divided by 1 2 3 4 5 6 9 10 12 15 18 20 25 30 36 45 50 60 73 75 79 90 100 146 150 158 180 219 225 237 292 300 316 365 395 438 450 474 657 711 730 790 876 900 948 1,095 1,185 1,314 1,422 1,460 1,580 1,825 1,975 2,190 2,370 2,628 2,844 3,285 3,555 3,650 3,950 4,380 4,740 5,475 5,767 5,925 6,570 7,110 7,300 7,900 10,950 11,534 11,850 13,140 14,220 16,425 17,301 17,775 21,900 23,068 23,700 28,835 32,850 34,602 35,550 51,903 57,670 65,700 69,204 71,100 86,505 103,806 115,340 144,175 173,010 207,612 259,515 288,350 346,020 432,525 519,030 576,700 865,050 1,038,060 1,297,575 1,730,100 2,595,150 and 5,190,300, with no remainder.
Since 5,190,300 cannot be divided by just 1 and 5,190,300, it is not a prime number.