| 166Er     | Half-life | Boson, 68p 98n |   |  
| Stable | Spin 0 Parity 1 |  
  This isotope is stable and thus has no decay products, so instead we show decay chains that lead down to it.   | 
| Atomic Weight | 165.930293061 |  
| Abundance | 33.503% |  
| Mass Excess | -64.931595MeV |  
| Binding Energy | 8.141992MeV |  
| Magnetic Moment | 0 μ |  
| Quadrupole Moment | N/A |  
 
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