Base 23 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
64: | \[{23^{64}-1\over22}\] | 28 × 3 × 5 × 17 × 53 × 193 × 257 × 3697 × 139921 × 623009 × 15887591750468908417<20> × 73169086596340605135996253341472193203073<41> |