Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 216: | \[2^{216}-1\] | 34 × 5 × 7 × 13 × 17 × 19 × 37 × 73 × 109 × 241 × 433 × 38737 × 87211 × 246241 × 262657 × 279073 × 33975937 × 138991501037953<15> |