Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 493: | \[2^{493}-1\] | 233 × 1103 × 2089 × 131071 × 3616649 × 10353001 × 9705965830054591736524329221017810064201521004178349356202268282852670198911141357299732185324536769414538999508070197039<121> |