A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3371592 can be evenly divided by 1 2 3 4 6 7 8 12 14 21 24 28 42 47 49 56 61 84 94 98 122 141 147 168 183 188 196 244 282 294 329 366 376 392 427 488 564 588 658 732 854 987 1,128 1,176 1,281 1,316 1,464 1,708 1,974 2,303 2,562 2,632 2,867 2,989 3,416 3,948 4,606 5,124 5,734 5,978 6,909 7,896 8,601 8,967 9,212 10,248 11,468 11,956 13,818 17,202 17,934 18,424 20,069 22,936 23,912 27,636 34,404 35,868 40,138 55,272 60,207 68,808 71,736 80,276 120,414 140,483 160,552 240,828 280,966 421,449 481,656 561,932 842,898 1,123,864 1,685,796 and 3,371,592, with no remainder.
Since 3,371,592 cannot be divided by just 1 and 3,371,592, it is not a prime number.