Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 154: | \[{20^{154}-1\over19}\] | 3 × 72 × 23 × 29 × 71 × 827 × 10529 × 32719 × 424016563147<12> × 10778947368421<14> × 11591111347512862858060061<26> × 94492701984716091424823399007224633473246602866536721<53> × 1210567578891427492816561347489923627502617025084966049153058402099173120000021<79> |