An aircraft turbine engine includes a turbine shaft having a first axis of rotation, a propulsion propeller having a second axis of rotation parallel to and spaced from the first axis, and a mechanical reduction gear coupled to the turbine shaft and rotating the propeller. The reduction gear has a sun gear connected to the turbine shaft, a ring gear, and at least two planet gears, each including a first external toothing that is meshed with an external toothing of the sun gear. A second external toothing is located within the ring gear and is meshed with an internal toothing of the ring gear.