It would be explosively unstable; the neutrons, which thanks to degeneracy, would be travelling at speeds of a fair fraction of $c$ would fly apart. After some tens of minutes they would almost all have decayed to electrons and protons. 

I provided some numbers here: http://physics.stackexchange.com/questions/10052/what-would-happen-to-a-teaspoon-of-neutron-star-material-if-released-on-earth