Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 678: | \[2^{678}-1\] | 32 × 7 × 227 × 3391 × 23279 × 48817 × 65993 × 156619 × 1868569 × 10113049 × 28448881 × 636190001 × 1066818132868207<16> × 491003369344660409<18> × 320021624768405574452943847<27> × 4760137992283599860814226997712217<34> × 8067670082858802084066104063317410636310881590473931569<55> |