Base 28 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 97: | \[{28^{97}-1\over27}\] | 971 × 11811109 × 1077512962627<13> × 709631467209875315796771044618306561153982255910640419690230176559964795222396960041765720122712469579101140989664777<117> |