LaTeX rendering of nice numbers isn't always nice

Useful internal functions to render some rational, algebraic numbers and exponential form of complex number aren't always producing the best result when used outside state rendering (**standalone** number rendering rather than **coefficients**). Now that we want to add a few other use cases we may want to fix that.
UPDATE:
Standalone rendering is now supported. The remaining part is only about improvements.
Previously:

No source file, test, or entry point is named. Start by locating the internal number-rendering functions and compare standalone rendering with coefficient rendering; confirm the desired improvements and acceptance examples with maintainers before changing behavior.

Written by the indexing model from the issue text.