# Inner electrons 80 # Outer electrons 58 # Protons 138 Abundance 0.25 An-Isotope 58:138 Approval Stats BE - Actual 1156.04 BE - Nucleon 8377.08 Decay 2EC 100 Element Cerium Half Life 4.4E+016 Y Mass Actual 137.91 Mass Calculated 139.08 Mass H Norm 136.84 Stability Stable
