primorijal (engl. primorial, od prime: primaran, prost i [fact]orial: faktorijel) (znak pn#) umnožak svih primbrojeva do n-tog primbroja pn, dakle:

npr.
2# = p1# = 2,
3# = p2# = 2 × 3 = 6,
5# = p3# = 2 × 3 × 5 = 30,
7# = p4# = 2 × 3 × 5 × 7 = 210,
11# = p5# = 2 × 3 × 5 × 7 × 11 = 2310,
13# = p6# = 2 × 3 × 5 × 7 × 11 × 13 = 30 030,
17# = p7# = 2 × 3 × 5 × 7 × 11 × 13 × 17 = 510 510.