| Atomic Mass | Mass Excess |
| 166.954696427169 amu | -42.2 MeV |
| Level energy (MeV) | Spin & parity | Half-life | Mode of decay | Branch ratio (%) | Decay energy (MeV) |
| Ground state | (+) | 19.9 S 0.5 | EC | 99.96 | 0 |
| Ground state | (+) | 19.9 S 0.5 | A | .04 | 4.668 |
There is no gamma-rays or the intensities are so weak!