Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 397: | \[2^{397}-1\] | 2383 × 6353 × 50023 × 53993 × 202471 × 5877983 × 814132872808522587940886856743<30> × 1234904213576000272542841146073<31> × 6597485910270326519900042655193<31> |