A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4763808 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 16 17 18 21 24 28 32 34 36 42 48 51 56 63 68 72 84 96 102 112 119 126 136 139 144 153 168 204 224 238 252 272 278 288 306 336 357 408 417 476 504 544 556 612 672 714 816 834 952 973 1,008 1,071 1,112 1,224 1,251 1,428 1,632 1,668 1,904 1,946 2,016 2,142 2,224 2,363 2,448 2,502 2,856 2,919 3,336 3,808 3,892 4,284 4,448 4,726 4,896 5,004 5,712 5,838 6,672 7,089 7,784 8,568 8,757 9,452 10,008 11,424 11,676 13,344 14,178 15,568 16,541 17,136 17,514 18,904 20,016 21,267 23,352 28,356 31,136 33,082 34,272 35,028 37,808 40,032 42,534 46,704 49,623 56,712 66,164 70,056 75,616 85,068 93,408 99,246 113,424 132,328 140,112 148,869 170,136 198,492 226,848 264,656 280,224 297,738 340,272 396,984 529,312 595,476 680,544 793,968 1,190,952 1,587,936 2,381,904 and 4,763,808, with no remainder.
Since 4,763,808 cannot be divided by just 1 and 4,763,808, it is not a prime number.