Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
553: | 127 × 2687 × 202029703 × 1113491139767<13> × 166153042787383<15> × 2311564013722765106562693324070664787462722331606243819658098082763568979086228833561077816432762779405410319245179999205262073<127> |