Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 720: | \[{21^{720}-1\over20}\] | 24 × 5 × 11 × 13 × 17 × 19 × 31 × 37 × 41 × 61 × 73 × 181 × 193 × 199 × 211 × 241 × 421 × 433 × 463 × 601 × 613 × 673 × 1693 × 2551 × 3121 × 3181 × 3361 × 7681 × 9391 × 9521 × 18181 × 40841 × 62897 × 97241 × 185641 × 300673 × 501001 × 658261 × 816769 × 1001713 × 1360861 × 3441241 × 12426241 × 22995281 × 25392481 × 33534961 × 40086001 × 41489011 × 57815101 × 85775383 × 518118697 × 808208209 × 920421641 × 3184193681 × 363230092241<12> × 4344847859197<13> × 415710882920521<15> × 1053606939618901<16> × 4116371120264449<16> × 22554946693833031<17> × 81967288802253121<17> × 4014083991013398361<19> × 41764164884102175841<20> × 12743948285379273103201<23> × 982245741266964256238881<24> × 82207575664095002495707981<26> × 84947863319467630678021906123321<32> × 303793280233949747866746506198881<33> × 13770093248814600891037861709841361<35> × 387296681442215139403864858966948878324061<42> × 711232550734200751494958531511588181663062004769<48> × 2135334117016238177166643352711488254647441970164671209065005534916910575135419083785586435904978340252668201<109> × [5869220610611513024215810754461970091003655181975784329090660646562632733778181436298566971954630322797954126287619535166545103163474529423531639530569103791894913934085639142151763029080198387060621573258241<208>] |