A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3442176 can be evenly divided by 1 2 3 4 6 8 9 12 16 18 24 27 32 36 48 54 64 72 81 83 96 108 128 144 162 166 192 216 249 256 288 324 332 384 432 498 512 576 648 664 747 768 864 996 1,152 1,296 1,328 1,494 1,536 1,728 1,992 2,241 2,304 2,592 2,656 2,988 3,456 3,984 4,482 4,608 5,184 5,312 5,976 6,723 6,912 7,968 8,964 10,368 10,624 11,952 13,446 13,824 15,936 17,928 20,736 21,248 23,904 26,892 31,872 35,856 41,472 42,496 47,808 53,784 63,744 71,712 95,616 107,568 127,488 143,424 191,232 215,136 286,848 382,464 430,272 573,696 860,544 1,147,392 1,721,088 and 3,442,176, with no remainder.
Since 3,442,176 cannot be divided by just 1 and 3,442,176, it is not a prime number.