Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
517: | \[2^{517}-1\] | 23 × 89 × 2351 × 4513 × 82721 × 13264529 × 387348809 × 1292800939332382943<19> × 270374114136830957955241<24> × 26302895729179572365768002599674239<35> × 5055472900700718446998992178766514487953008646383<49> |