Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 165: | \[{21^{165}-1\over20}\] | 5 × 67 × 211 × 331 × 463 × 881 × 3301 × 9391 × 18181 × 40841 × 372901 × 5664205361<10> × 182894303461<12> × 17513875027111<14> × 28503846834226831<17> × 270573999780463721<18> × 54598616218616435702441<23> × 3955202198062795629622003<25> × 237967900696723393143507690151891<33> × 12445053671159143233988565211478891<35> |