Base 5 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 139: | \[{5^{139}-1\over4}\] | 21521602057721<14> × 6789441546024769741462601111<28> × 24550591546653776667941845268908441565415743319193209001<56> |