A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4444308 can be evenly divided by 1 2 3 4 6 9 11 12 18 22 27 29 33 36 43 44 54 58 66 81 86 87 99 108 116 129 132 162 172 174 198 258 261 297 319 324 348 387 396 473 516 522 594 638 774 783 891 946 957 1,044 1,161 1,188 1,247 1,276 1,419 1,548 1,566 1,782 1,892 1,914 2,322 2,349 2,494 2,838 2,871 3,132 3,483 3,564 3,741 3,828 4,257 4,644 4,698 4,988 5,676 5,742 6,966 7,482 8,514 8,613 9,396 11,223 11,484 12,771 13,717 13,932 14,964 17,028 17,226 22,446 25,542 25,839 27,434 33,669 34,452 38,313 41,151 44,892 51,084 51,678 54,868 67,338 76,626 82,302 101,007 103,356 123,453 134,676 153,252 164,604 202,014 246,906 370,359 404,028 493,812 740,718 1,111,077 1,481,436 2,222,154 and 4,444,308, with no remainder.
Since 4,444,308 cannot be divided by just 1 and 4,444,308, it is not a prime number.