Why can't we reverse hashes?

This is an easy example of "why can't we reverse hashes?"
In this video, I finally figure out the result of factorization.

However, what if the number becomes larger than now?
Even with super computer, we may not get the result finally.

The factorization is the good tool for hash function.
#reverseofhashes #hashfunctioncryptography

[TheOiseau]

But this has nothing to do with why we can't reverse hashes. Hashes are made to be irreversible, no matter how much computing power you have, since the data is collasped down into a short digital signature. The factorisation thing in this video is why we can't crack RSA, which is a cypher algorithm — not a hash function.

[PRED]

so, cause digit number is longer in SHA256, the factorization of large number will take longer time. That’s the source of safety.