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								id: 5900f4c31000cf542c50ffd5
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								title: 'Problem 342: The totient of a square is a cube'
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								challengeType: 5
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 302001
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								dashedName: problem-342-the-totient-of-a-square-is-a-cube
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								---
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								# --description--
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								Consider the number 50.
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											2021-07-29 19:14:22 +02:00
										 
									 
								 
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								${50}^2 = 2500 = 2^2 × 5^4$, so $φ(2500) = 2 × 4 × 5^3 = 8 × 5^3 = 2^3 × 5^3$. $φ$ denotes Euler's totient function.
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								So 2500 is a square and $φ(2500)$ is a cube.
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								Find the sum of all numbers $n$, $1 < n < {10}^{10}$ such that $φ(n^2)$ is a cube.
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								# --hints--
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								`totientOfSquare()` should return `5943040885644`.
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								```js
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								assert.strictEqual(totientOfSquare(), 5943040885644);
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								```
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								# --seed--
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								## --seed-contents--
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								```js
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								function totientOfSquare() {
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								  return true;
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								}
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								totientOfSquare();
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								```
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								# --solutions--
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								```js
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								// solution required
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								```
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