Library for working with giant numbers on Qt4?

Question

Qt

I am writing an implementation of the RSA algorithm (this is the laboratory work), but the size of the standard variables is not enough. Does qt have libraries for working with very large numbers (which would take a whole sheet of A4 to write on paper)? I saw it in the dotnet, but I didn't find anything for the kite.
In general, what is there for C ++ under Linux?