A compressor has a rotor. The rotor includes a plurality of impellers that include a disk having a solid structure having a buried center, and are adjacent to each other in an axial direction, and a plurality of bolts for fixing the plurality of impellers together. The disk has a disk surface facing the axial direction and a bolt hole penetrating the disk at a position deviated outward from an axis in a radial direction. The disk surface includes a contact surface of which at least a part is located outside the bolt hole in the radial direction, and a non-contact surface which is a region inside the contact surface in the radial direction.