A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5748120 can be evenly divided by 1 2 3 4 5 6 7 8 9 10 12 14 15 18 20 21 24 28 30 35 36 40 42 45 56 60 63 70 72 84 90 105 120 126 140 168 180 210 252 280 315 360 420 504 630 840 1,260 2,281 2,520 4,562 6,843 9,124 11,405 13,686 15,967 18,248 20,529 22,810 27,372 31,934 34,215 41,058 45,620 47,901 54,744 63,868 68,430 79,835 82,116 91,240 95,802 102,645 127,736 136,860 143,703 159,670 164,232 191,604 205,290 239,505 273,720 287,406 319,340 383,208 410,580 479,010 574,812 638,680 718,515 821,160 958,020 1,149,624 1,437,030 1,916,040 2,874,060 and 5,748,120, with no remainder.
Since 5,748,120 cannot be divided by just 1 and 5,748,120, it is not a prime number.