A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3304290 can be evenly divided by 1 2 3 5 6 10 11 15 17 19 22 30 31 33 34 38 51 55 57 62 66 85 93 95 102 110 114 155 165 170 186 187 190 209 255 285 310 323 330 341 374 418 465 510 527 561 570 589 627 646 682 930 935 969 1,023 1,045 1,054 1,122 1,178 1,254 1,581 1,615 1,705 1,767 1,870 1,938 2,046 2,090 2,635 2,805 2,945 3,135 3,162 3,230 3,410 3,534 3,553 4,845 5,115 5,270 5,610 5,797 5,890 6,270 6,479 7,106 7,905 8,835 9,690 10,013 10,230 10,659 11,594 12,958 15,810 17,391 17,670 17,765 19,437 20,026 21,318 28,985 30,039 32,395 34,782 35,530 38,874 50,065 53,295 57,970 60,078 64,790 86,955 97,185 100,130 106,590 110,143 150,195 173,910 194,370 220,286 300,390 330,429 550,715 660,858 1,101,430 1,652,145 and 3,304,290, with no remainder.
Since 3,304,290 cannot be divided by just 1 and 3,304,290, it is not a prime number.