A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7890204 can be evenly divided by 1 2 3 4 6 7 12 14 21 28 29 41 42 58 79 82 84 87 116 123 158 164 174 203 237 246 287 316 348 406 474 492 553 574 609 812 861 948 1,106 1,148 1,189 1,218 1,659 1,722 2,212 2,291 2,378 2,436 3,239 3,318 3,444 3,567 4,582 4,756 6,478 6,636 6,873 7,134 8,323 9,164 9,717 12,956 13,746 14,268 16,037 16,646 19,434 22,673 24,969 27,492 32,074 33,292 38,868 45,346 48,111 49,938 64,148 68,019 90,692 93,931 96,222 99,876 136,038 187,862 192,444 272,076 281,793 375,724 563,586 657,517 1,127,172 1,315,034 1,972,551 2,630,068 3,945,102 and 7,890,204, with no remainder.
Since 7,890,204 cannot be divided by just 1 and 7,890,204, it is not a prime number.