Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 486: | \[{21^{486}-1\over20}\] | 2 × 11 × 19 × 37 × 109 × 163 × 199 × 421 × 463 × 487 × 613 × 1783 × 5077 × 17497 × 110323 × 4779433 × 10012573 × 85775383 × 7429452749713<13> × 7101932659132249<16> × 1276510846672627851615095313889284277672664124131976230679615049<64> × 251097226443098886970664441840231990201201851332912023687544574398706423<72> × [1581175409002158649464777448054823775135618893624954470172510070414484570779538316601823215072601727352541419382890036109292377250306724929848837752543155144065910359753944622321958642249728833690663930134377<208>] × [32508489134371602947325452006986922075320265036137764382502216988213895323005737784954552102688141878939256568259641975725630438915767245472318133084604624899450811325447765194097430787950460872285665833373668249<212>] |