At some point gravitational forces start counteracting centrifugal forces again, so density means a lot. Apparently the fastest-spinning neutron star known so f

At some point gravitational forces start counteracting centrifugal forces again, so density means a lot. Apparently the fastest-spinning neutron star known so far spins at about 716 rotations per second. (see https://en.wikipedia.org/wiki/Neutron_star https://en.wikipedia.org/wiki/Neutron_star)