A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4427808 can be evenly divided by 1 2 3 4 6 7 8 11 12 14 16 21 22 24 28 32 33 42 44 48 56 66 77 84 88 96 112 132 154 168 176 224 231 264 308 336 352 462 528 599 616 672 924 1,056 1,198 1,232 1,797 1,848 2,396 2,464 3,594 3,696 4,193 4,792 6,589 7,188 7,392 8,386 9,584 12,579 13,178 14,376 16,772 19,168 19,767 25,158 26,356 28,752 33,544 39,534 46,123 50,316 52,712 57,504 67,088 79,068 92,246 100,632 105,424 134,176 138,369 158,136 184,492 201,264 210,848 276,738 316,272 368,984 402,528 553,476 632,544 737,968 1,106,952 1,475,936 2,213,904 and 4,427,808, with no remainder.
Since 4,427,808 cannot be divided by just 1 and 4,427,808, it is not a prime number.