A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5545400 can be evenly divided by 1 2 4 5 7 8 10 14 17 20 25 28 34 35 40 50 56 68 70 85 100 119 136 140 170 175 200 233 238 280 340 350 425 466 476 595 680 700 850 932 952 1,165 1,190 1,400 1,631 1,700 1,864 2,330 2,380 2,975 3,262 3,400 3,961 4,660 4,760 5,825 5,950 6,524 7,922 8,155 9,320 11,650 11,900 13,048 15,844 16,310 19,805 23,300 23,800 27,727 31,688 32,620 39,610 40,775 46,600 55,454 65,240 79,220 81,550 99,025 110,908 138,635 158,440 163,100 198,050 221,816 277,270 326,200 396,100 554,540 693,175 792,200 1,109,080 1,386,350 2,772,700 and 5,545,400, with no remainder.
Since 5,545,400 cannot be divided by just 1 and 5,545,400, it is not a prime number.