Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 236: | \[2^{236}-1\] | 3 × 5 × 1181 × 2833 × 3541 × 37171 × 157649 × 174877 × 179951 × 5521693 × 1824726041 × 104399276341<12> × 3203431780337<13> |