I assume the standard BIP0039 wordlist is used here. So you have 2048 words, repetition is also allowed.

So you have a total of

2048! / (2048−12)! =  5271537971301488476000309317528177868800 permutations.

Well, good luck with landing on any wallets that have funds in.

It takes time to get the private key, derive the public key and addresses and then check them for balance.