| Atomic Mass | Mass Excess |
| 258.109394172309 amu | 101.9 MeV |
| Level energy (MeV) | Spin & parity | Half-life | Mode of decay | Branch ratio (%) | Decay energy (MeV) |
| Ground state | 4.4 S +0.9-0.6 | A | 67 | 9.55 | |
| Ground state | 4.4 S +0.9-0.6 | EC | 33 | 5.5 | |
| Ground state | 4.4 S +0.9-0.6 | SF | <1.00 | 0 | |
| Ground state | 20 S 10 | EC | 100 | 5.5 |
| Decay mode | Half-life | Gamma-ray energy (keV) | Intensity (%) |
| A | 4.4 S +0.9-0.6 | 95 | 18.8+- 2.0 |