There are several reasons why a protein would have
hypothetical designation. For hypothetical proteins, it is not always clear that they are real proteins to begin with, either because of their unusual composition or relatively short length. Next, they may be truly uncharacterized and have no discernable sequence similarity to other characterized proteins. Or they may have distant homology to other characterized proteins, but one has to dig deep to uncover it as simple sequence comparisons (BLAST-like) will not detect it. Finally, a protein may have been in one of the above categories when the original annotation was done, and its annotation was never updated.
I am assuming that the link below is of your protein:
If so, click on the link at the far right that says
Identify Conserved Domains and you'll see that this protein has two domains that indicate a function in nucleic acid binding and integration. That may or may not help you directly, but it is better than not knowing anything.