Base 5 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 161: | \[{5^{161}-1\over4}\] | 8971 × 19531 × 332207361361<12> × 146938674667821698939790140544890177855634270543389059647071922199454271085510730718993828121<93> |