A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3306450 can be evenly divided by 1 2 3 5 6 7 10 14 15 21 25 30 35 42 47 50 67 70 75 94 105 134 141 150 175 201 210 235 282 329 335 350 402 469 470 525 658 670 705 938 987 1,005 1,050 1,175 1,407 1,410 1,645 1,675 1,974 2,010 2,345 2,350 2,814 3,149 3,290 3,350 3,525 4,690 4,935 5,025 6,298 7,035 7,050 8,225 9,447 9,870 10,050 11,725 14,070 15,745 16,450 18,894 22,043 23,450 24,675 31,490 35,175 44,086 47,235 49,350 66,129 70,350 78,725 94,470 110,215 132,258 157,450 220,430 236,175 330,645 472,350 551,075 661,290 1,102,150 1,653,225 and 3,306,450, with no remainder.
Since 3,306,450 cannot be divided by just 1 and 3,306,450, it is not a prime number.