A neutron star is so dense that one teaspoon (5 millilitres) of its material would have a mass over 5×1012 kg or 5,500,000,000 tons. About 900 pyramids of Giza.

The resulting force of gravity is so strong that if an object were to fall from just one meter high it would hit the surface of the neutron star at around 2,000 kilometres per second, or 4.3 million miles per hour.

See related question.