Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 489: | \[2^{489}-1\] | 7 × 150287 × 704161 × 836191 × 110211473 × 355307401 × 27669118297<11> × 116539854237679<15> × 36230454570129675721<20> × 619079222361672204943<21> × 911066556314339913468351173796888655666135594657<48> |