A planetary roller screw comprising: a spindle having a male thread , a nut having a female thread , and planetary rollers arranged between the spindle and the nut and each including a male thread which engages both the male thread of the spindle and the female thread of the nut , wherein the spindle and the planetary rollers each include external toothing , the external toothing of the spindle meshing with the external toothing of the planetary rollers , wherein the external toothing of the spindle is engaged in the male thread of the spindle and/or the external toothing of the planetary rollers is engaged in the male thread of the planetary rollers , so that the spindle and/or the planetary rollers include an overlapping section in which the respective male thread and the respective external toothing overlap such that a relative axial displacement between the spindle and the planetary rollers is enabled, wherein the planetary roller screw further includes a ring gear having internal toothing , wherein the nut is non-rotatable with respect to the ring gear , and wherein the external toothing of the planetary rollers meshes with the internal toothing of the ring gear , and wherein the planetary roller screw comprises a housing on which the spindle is rotatably supported, characterized in that the ring gear is non rotatable and axially displaceable with respect to the housing , wherein furthermore the nut is supported axially displaceably with respect to the ring gear , and wherein diameter ratios between spindle , planetary rollers and nut are selected such that, upon rotation of the spindle , both a relative axial displacement of the ring gear with respect to the housing and a relative axial displacement of the nut with respect to the ring gear take place. a spindle having a male thread , a nut having a female thread , and planetary rollers arranged between the spindle and the nut and each including a male thread which engages both the male thread of the spindle and the female thread of the nut , wherein the spindle and the planetary rollers each include external toothing , the external toothing of the spindle meshing with the external toothing of the planetary rollers , wherein the external toothing of the spindle is engaged in the male thread of the spindle and/or the external toothing of the planetary rollers is engaged in the male thread of the planetary rollers , so that the spindle and/or the planetary rollers include an overlapping section in which the respective male thread and the respective external toothing overlap such that a relative axial displacement between the spindle and the planetary rollers is enabled, wherein the planetary roller screw further includes a ring gear having internal toothing , wherein the nut is non-rotatable with respect to the ring gear , and wherein the external toothing of the planetary rollers meshes with the internal toothing of the ring gear , and wherein the planetary roller screw comprises a housing on which the spindle is rotatably supported, characterized in that the ring gear is non rotatable and axially displaceable with respect to the housing , wherein furthermore the nut is supported axially displaceably with respect to the ring gear , and wherein diameter ratios between spindle , planetary rollers and nut are selected such that, upon rotation of the spindle , both a relative axial displacement of the ring gear with respect to the housing and a relative axial displacement of the nut with respect to the ring gear take place. <EOS>