A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5304180 can be evenly divided by 1 2 3 4 5 6 7 10 12 14 15 20 21 28 30 35 42 60 70 73 84 105 140 146 173 210 219 292 346 365 420 438 511 519 692 730 865 876 1,022 1,038 1,095 1,211 1,460 1,533 1,730 2,044 2,076 2,190 2,422 2,555 2,595 3,066 3,460 3,633 4,380 4,844 5,110 5,190 6,055 6,132 7,266 7,665 10,220 10,380 12,110 12,629 14,532 15,330 18,165 24,220 25,258 30,660 36,330 37,887 50,516 63,145 72,660 75,774 88,403 126,290 151,548 176,806 189,435 252,580 265,209 353,612 378,870 442,015 530,418 757,740 884,030 1,060,836 1,326,045 1,768,060 2,652,090 and 5,304,180, with no remainder.
Since 5,304,180 cannot be divided by just 1 and 5,304,180, it is not a prime number.