A positively chargeable toner includes toner particles. The toner particles each include a toner mother particle containing a binder resin, and an external additive adhering to a surface of the toner mother particle. The external additive includes specific silica particles, specific titania particles, and specific crosslinked resin particles. The specific silica particles each include a silica base, and a first surface treatment layer present on a surface of the silica base. The first surface treatment layer has an alkyl group having a carbon number of at least 8 and no greater than 16, and an amino group. The specific titania particles each include a titania base, and a second surface treatment layer present on a surface of the titania base. The second surface treatment layer has an alkyl group having a carbon number of at least 3 and no greater than 8.