[REQUEST] how many possible attachment combinations are there in battlefield 4

My friends and I were arguing if BF4 had more possible weapon combinations than borderlands 2s 17,500,000. While I’m bad at math if you were to take each gun and calculate the total number of ways which you could configure it (1, 2, 3, and 4 attachment set ups) and then do it for every gun in the game (including pistols which only have 3 attachment slots) you would find it to be more than borderlands 2. Does anyone want to help figure this out?