Looking at http://www.frankswebspace.org.uk/ScienceAndMaths/physics/physicsGCE/nuclearImages/islandOfStability.jpg , one of the patterns I see is that even numbers of protons and neutrons are systematically more stable than odd numbers. So that might answer the specific part of your question about its neighbors. (As to why even numbers, I don't know but I bet it's related to spins.)

EDIT: Apparently this is enough of a thing that it even has its own Wikipedia page. http://en.wikipedia.org/wiki/Even_and_odd_atomic_nuclei