Base 22 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
61: | \[{22^{61}-1\over21}\] | 733 × 188369 × 13531997 × 1078645984686904783<19> × 182477786660053773085442131722484638881547011413<48> |