Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 677: | \[2^{677}-1\] | 1943118631 × 531132717139346021081<21> × 978146583988637765536217<24> × 53625112691923843508117942311516428173021903300344567<53> × 11583306121194302925666610180475654822154587629577979400456857120235319057709961541850271218784399<98> |