There is provided a roller including: a shaft, and an elastic body portion that is provided on an outer peripheral surface of the shaft, in which the elastic body portion includes a plurality of first recessed portions which are provided on one side of the roller in a shaft mounting direction at intervals in a circumferential direction of the roller and each have a bottom portion, and a plurality of second recessed portions which are provided on the other side of the roller in the shaft mounting direction at intervals in the circumferential direction of the roller and each have a bottom portion, and in which each of the first recessed portions is positioned between the adjacent second recessed portions in the circumferential direction of the roller in the side view of the roller in the shaft mounting direction.