Base 28 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 73: | \[{28^{73}-1\over27}\] | 439 × 1924218827 × 1395719566812246425341583<25> × 33669332701243432328246627927<29> × 4096574600013882571943794643612275539257<40> |