A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 7610688 can be evenly divided by 1 2 3 4 6 8 9 12 16 18 24 32 36 48 64 72 73 96 144 146 181 192 219 288 292 362 438 543 576 584 657 724 876 1,086 1,168 1,314 1,448 1,629 1,752 2,172 2,336 2,628 2,896 3,258 3,504 4,344 4,672 5,256 5,792 6,516 7,008 8,688 10,512 11,584 13,032 13,213 14,016 17,376 21,024 26,064 26,426 34,752 39,639 42,048 52,128 52,852 79,278 104,256 105,704 118,917 158,556 211,408 237,834 317,112 422,816 475,668 634,224 845,632 951,336 1,268,448 1,902,672 2,536,896 3,805,344 and 7,610,688, with no remainder.
Since 7,610,688 cannot be divided by just 1 and 7,610,688, it is not a prime number.