Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 121: | \[{15^{121}-1\over14}\] | 67 × 463 × 2333 × 7019 × 8537 × 60966770930329903<17> × 5627184418701839214950691388503744769436522116776893<52> × 973596293359690050660589564381789969621086099491919940801<57> |