Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 186: | \[{21^{186}-1\over20}\] | 2 × 11 × 373 × 421 × 463 × 1303 × 78059 × 70672747 × 185040613 × 4035955783 × 4540713283<10> × 3936833990413<13> × 783622559828503<15> × 272581865551637989<18> × 5490236844314625181981860471139<31> × 56748249908554278937564172324714039<35> × 545433510558480076170784902124529747359<39> × 7687249112242592598176964045333142849438561<43> |