The fast spin of near-Earth asteroid (455213) 2001 OE84, revisited after 14 years: Constraints on internal structure

•We confirmed the fast spin of (455213) 2001OE84 is 0.486542 h with no change since first measured.•Current estimations of asteroid cohesion are insufficient to maintain an intact rubble pile.•We argue that a monolithic asteroid is the most plausible model.•Constraints applied from collision probabilities and spin evolution, set an age for OE84 between 2-10 Myrs.