A bicycle includes an electrical auxiliary drive, including an electric motor, a battery for storing electrical energy, which battery is connected to the electric motor, a crank mechanism having pedal cranks, which are mounted on a pedal crankshaft disposed about a crank axis, so as to be able to rotate, and a planetary gear for driving the bicycle both by the electric motor and by the muscle power of a driver, the planetary gear and the electric motor being disposed about the pedal crankshaft of the crank mechanism.