Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 98: | \[{20^{98}-1\over19}\] | 3 × 73 × 29 × 71 × 827 × 10529 × 32719 × 269737651 × 2488859795549<13> × 6551154092925933298930251891324599<34> × 628292358238289452269193508271835428805485714102857143<54> |