Did you know the largest known repunit probable prime has over 8 million digits—and every single one is a “1”?
This incredible number, called R₈,₁₇₇,₂₀₇, is written as:
(10⁸¹⁷⁷²⁰⁷ − 1) ÷ 9
It’s a record-breaking giant in number theory, with 8,177,207 consecutive “1”s.
