Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 141: | \[{21^{141}-1\over20}\] | 463 × 49727 × 227011 × 38571961 × 75042551 × 158545759 × 5298873343<10> × 62754239731<11> × 26050530648193<14> × 471375279539413<15> × 85297241991463563433<20> × 9794718038248648833094153<25> × 16557682722621587651041257050155686425265489802868579623<56> |