A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3448170 can be evenly divided by 1 2 3 5 6 9 10 11 15 18 22 27 30 33 43 45 54 55 66 81 86 90 99 110 129 135 162 165 198 215 243 258 270 297 330 387 405 430 473 486 495 594 645 729 774 810 891 946 990 1,161 1,215 1,290 1,419 1,458 1,485 1,782 1,935 2,322 2,365 2,430 2,673 2,838 2,970 3,483 3,645 3,870 4,257 4,455 4,730 5,346 5,805 6,966 7,095 7,290 8,019 8,514 8,910 10,449 11,610 12,771 13,365 14,190 16,038 17,415 20,898 21,285 25,542 26,730 31,347 34,830 38,313 40,095 42,570 52,245 62,694 63,855 76,626 80,190 104,490 114,939 127,710 156,735 191,565 229,878 313,470 344,817 383,130 574,695 689,634 1,149,390 1,724,085 and 3,448,170, with no remainder.
Since 3,448,170 cannot be divided by just 1 and 3,448,170, it is not a prime number.