Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 396: | \[{21^{396}-1\over20}\] | 22 × 112 × 13 × 17 × 19 × 23 × 37 × 61 × 67 × 89 × 199 × 397 × 421 × 463 × 613 × 661 × 1693 × 3181 × 3499 × 6073 × 16633 × 28513 × 33199 × 1130581 × 10362529 × 85775383 × 4344847859197<13> × 17513875027111<14> × 87989435079877<14> × 724051700079313<15> × 782006960636353<15> × 146354764854514987<18> × 4718573764413203147069<22> × 3955202198062795629622003<25> × 2809844133434751558300752991125417401<37> × 107148448424462133146016309681831670177<39> × 188145268678304791443009491673532813732054627291<48> × 19050347137684245501074582624627605674546940303323636856235442615869112421<74> × 24996088249541157288783680188037792703582928378821408321606722793998163081176971217591697247876969771116056350846501<116> |