I guess it's obvious that one human being can't know everything. One way to approach the question though is to look at human beings collectively as a model of computing, and assume our species lives on forever. Then it becomes a more interesting question to me. One question is the problem of taking information then decomposing it into smaller atomic parts that are each understandable, and then take those construct the objects one level higher (can we understand how to do that), and then keep going, making use of abstraction and treating abstract objects as black boxes. This is basically how we manage complexity and are able to build complex things like modern computers and other things. So how far can this take us?
This to me is an interesting topic for mathematics as well. Even now some people submit proofs hundreds of pages long that few can understand or determine the correctness.
As AI begins discovering things and we rely on those discoveries, it will be nice if humans can keep up and understand those discoveries too. So we will need an effective way to communicate with AI. I think, given the challenges we have communicating mathematical proofs that are 100% objectively verifiable, it would be a good start yo revolutionize how we write proofs so that others can systematically break them down, understand them, and verify them. I think we need better formalization and standards for how we construct and communicate abstractions. Once we've achieved this, it could be applied for communicating with AI probably.
If you take human beings collectively, and compare that with computers, then I think humans together might have at least the same power in trrms of computability. But one individual can only do and learn so much.
Edit; Actually it is probably the case that even an atomic object could be too large to fit in any human brain whereas a computer could scale up. At that point it is s question if multiple humans can team up to tackle a single vast atomic/non-decomposable chunk of information. Also even the parameters of one black box can be too vast.