Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 228: | \[{21^{228}-1\over20}\] | 22 × 11 × 13 × 17 × 61 × 229 × 421 × 457 × 463 × 3181 × 3877 × 304609 × 609673 × 5285953 × 67505443 × 12061389013<11> × 64793186833<11> × 832365876613<12> × 54921106624003<14> × 987749814642143197<18> × 1168393184916024427650240126995059<34> × 1244541772187848099210936765314595053007129<43> × 3794540985952206860593938878074866571399837<43> × 759335118134710886340813211993720491870188616648988898625881069924137<69> |