A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3734808 can be evenly divided by 1 2 3 4 6 7 8 11 12 14 21 22 24 28 33 42 43 44 47 56 66 77 84 86 88 94 129 132 141 154 168 172 188 231 258 264 282 301 308 329 344 376 462 473 516 517 564 602 616 658 903 924 946 987 1,032 1,034 1,128 1,204 1,316 1,419 1,551 1,806 1,848 1,892 1,974 2,021 2,068 2,408 2,632 2,838 3,102 3,311 3,612 3,619 3,784 3,948 4,042 4,136 5,676 6,063 6,204 6,622 7,224 7,238 7,896 8,084 9,933 10,857 11,352 12,126 12,408 13,244 14,147 14,476 16,168 19,866 21,714 22,231 24,252 26,488 28,294 28,952 39,732 42,441 43,428 44,462 48,504 56,588 66,693 79,464 84,882 86,856 88,924 113,176 133,386 155,617 169,764 177,848 266,772 311,234 339,528 466,851 533,544 622,468 933,702 1,244,936 1,867,404 and 3,734,808, with no remainder.
Since 3,734,808 cannot be divided by just 1 and 3,734,808, it is not a prime number.