A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5307264 can be evenly divided by 1 2 3 4 6 8 9 12 16 17 18 24 32 34 36 48 51 64 68 72 96 102 128 136 144 153 192 204 271 272 288 306 384 408 542 544 576 612 813 816 1,084 1,088 1,152 1,224 1,626 1,632 2,168 2,176 2,439 2,448 3,252 3,264 4,336 4,607 4,878 4,896 6,504 6,528 8,672 9,214 9,756 9,792 13,008 13,821 17,344 18,428 19,512 19,584 26,016 27,642 34,688 36,856 39,024 41,463 52,032 55,284 73,712 78,048 82,926 104,064 110,568 147,424 156,096 165,852 221,136 294,848 312,192 331,704 442,272 589,696 663,408 884,544 1,326,816 1,769,088 2,653,632 and 5,307,264, with no remainder.
Since 5,307,264 cannot be divided by just 1 and 5,307,264, it is not a prime number.