Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 190: | \[{21^{190}-1\over20}\] | 2 × 5 × 11 × 191 × 40841 × 185641 × 205391 × 609673 × 12061389013<11> × 18806124191<11> × 19449969211<11> × 54921106624003<14> × 619598441951897251<18> × 987749814642143197<18> × 2522688573446019221<19> × 4962575794097659196896553056277931780683391554141<49> × 224946077318312621202864321882925242281698103188770132390249098696465091061151<78> |