PARI/GP is a widely used computer algebra system designed for fast computations in number theory, including factorizations, algebraic number theory, elliptic curves, modular forms, L functions, etc. The app also contains useful functions to compute with mathematical entities such as matrices, polynomials, power series, algebraic numbers, etc., and a lot of transcendental functions. PARI is also available as a C library to allow for faster computations.
