--- id: 5900f3f11000cf542c50ff03 title: 'Problem 132: Large repunit factors' challengeType: 5 forumTopicId: 301760 dashedName: problem-132-large-repunit-factors --- # --description-- A number consisting entirely of ones is called a repunit. We shall define $R(k)$ to be a repunit of length $k$. For example, $R(10) = 1111111111 = 11 × 41 × 271 × 9091$, and the sum of these prime factors is 9414. Find the sum of the first forty prime factors of $R({10}^9)$. # --hints-- `largeRepunitFactors()` should return `843296`. ```js assert.strictEqual(largeRepunitFactors(), 843296); ``` # --seed-- ## --seed-contents-- ```js function largeRepunitFactors() { return true; } largeRepunitFactors(); ``` # --solutions-- ```js // solution required ```