Rotor and electric motor with such a rotor

The rotor has a base body (2) comprising a cylinder-shaped peripheral wall (3) and a front-sided covering wall (4) that is connected with the peripheral wall in a longitudinal direction by using an outer wall transition section. A rotor shaft (5) is centrically connected with the covering layer and projects axially into a rotor area (6) surrounded by the peripheral wall. The base body and the rotor shaft are manufactured as a single piece from an aluminum alloy, where the rotor shaft is partially designed as a hollow shaft in an area running out from the covering wall. An independent claim is also included for an electric motor comprising a rotor and a stator.