--- id: 5900f5041000cf542c510016 challengeType: 5 title: 'Problem 407: Idempotents' videoUrl: '' localeTitle: '' --- ## Description undefined ## Instructions undefined ## Tests ```yml tests: - text: '' testString: 'assert.strictEqual(euler407(), 39782849136421, "euler407() should return 39782849136421.");' ``` ## Challenge Seed ```js function euler407() { // Good luck! return true; } euler407(); ``` ## Solution ```js // solution required ```
euler407()