A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5028300 can be evenly divided by 1 2 3 4 5 6 9 10 12 15 18 20 25 30 36 37 45 50 60 74 75 90 100 111 148 150 151 180 185 222 225 300 302 333 370 444 450 453 555 604 666 740 755 900 906 925 1,110 1,332 1,359 1,510 1,665 1,812 1,850 2,220 2,265 2,718 2,775 3,020 3,330 3,700 3,775 4,530 5,436 5,550 5,587 6,660 6,795 7,550 8,325 9,060 11,100 11,174 11,325 13,590 15,100 16,650 16,761 22,348 22,650 27,180 27,935 33,300 33,522 33,975 45,300 50,283 55,870 67,044 67,950 83,805 100,566 111,740 135,900 139,675 167,610 201,132 251,415 279,350 335,220 419,025 502,830 558,700 838,050 1,005,660 1,257,075 1,676,100 2,514,150 and 5,028,300, with no remainder.
Since 5,028,300 cannot be divided by just 1 and 5,028,300, it is not a prime number.