Two decades of intense R&D at Wolfram Research have given Mathematica by far the world's broadest and deepest coverage of special functions—and greatly expanded the whole domain of practical closed-form solutions. Often using original results and methods, all special functions in Mathematica support arbitrary-precision evaluation for all complex values of parameters, arbitrary series expansion even at branch points, and an immense web of exact relations, transformations, and simplifications.
N — numerical evaluation to any precision
FunctionExpand — expand in terms of simpler functions
FullSimplify — apply full symbolic simplification
FindRoot — find numerical zeros of functions