A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2544300 can be evenly divided by 1 2 3 4 5 6 9 10 11 12 15 18 20 22 25 30 33 36 44 45 50 55 60 66 75 90 99 100 110 132 150 165 180 198 220 225 257 275 300 330 396 450 495 514 550 660 771 825 900 990 1,028 1,100 1,285 1,542 1,650 1,980 2,313 2,475 2,570 2,827 3,084 3,300 3,855 4,626 4,950 5,140 5,654 6,425 7,710 8,481 9,252 9,900 11,308 11,565 12,850 14,135 15,420 16,962 19,275 23,130 25,443 25,700 28,270 33,924 38,550 42,405 46,260 50,886 56,540 57,825 70,675 77,100 84,810 101,772 115,650 127,215 141,350 169,620 212,025 231,300 254,430 282,700 424,050 508,860 636,075 848,100 1,272,150 and 2,544,300, with no remainder.
Since 2,544,300 cannot be divided by just 1 and 2,544,300, it is not a prime number.