A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3799488 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 64 66 77 84 88 96 112 132 154 168 176 192 224 231 257 264 308 336 352 448 462 514 528 616 672 704 771 924 1,028 1,056 1,232 1,344 1,542 1,799 1,848 2,056 2,112 2,464 2,827 3,084 3,598 3,696 4,112 4,928 5,397 5,654 6,168 7,196 7,392 8,224 8,481 10,794 11,308 12,336 14,392 14,784 16,448 16,962 19,789 21,588 22,616 24,672 28,784 33,924 39,578 43,176 45,232 49,344 57,568 59,367 67,848 79,156 86,352 90,464 115,136 118,734 135,696 158,312 172,704 180,928 237,468 271,392 316,624 345,408 474,936 542,784 633,248 949,872 1,266,496 1,899,744 and 3,799,488, with no remainder.
Since 3,799,488 cannot be divided by just 1 and 3,799,488, it is not a prime number.