The product of primes p_n # congruent product_(k = 1)^n p_k, with p_n the nth prime, is called the primorial function, by analogy with the factorial function. Its logarithm is closely related to the Chebyshev function θ(x).

Artin's constant | Chebyshev functions | Euler product | Feller-Tornier constant | Heath-Brown-Moroz constant | infinite product | Mertens theorem | Murata's constant | prime constellation | prime formulas | prime number | prime sums | primorial | primorial prime | quadratic class number constant | Sarnak's constant | Stephens' constant | totient summatory function | twin primes constant