For a 12 word/128 bit BIP-39 seed phase, it will be 10^38 possible seed phrases, and for a 24 word/256 bit seed phrase, it would be 10^77 possible seed phrases; both ridiculously large numbers, but both still tiny when compared to 10^130.

Sources: 1 - https://foundationdevices.com/2023/06/make-12-words-the-standard/ 2 - https://onlinetools.com/number/convert-number-to-power-of-ten 3 - https://bard.google.com/ (to check my math conversions)