freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/project-euler/problem-248-numbers-for-which-eulers-totient-function-equals-13.english.md

---
id: 5900f4651000cf542c50ff77
challengeType: 5
title: 'Problem 248: Numbers for which Euler’s totient function equals 13!'
---

## Description
<section id='description'>
The first number n for which φ(n)=13! is 6227180929.
Find the 150,000th such number.
</section>

## Instructions
<section id='instructions'>

</section>

## Tests
<section id='tests'>

```yml
tests:
  - text: <code>euler248()</code> should return 23507044290.
    testString: assert.strictEqual(euler248(), 23507044290, '<code>euler248()</code> should return 23507044290.');

```

</section>

## Challenge Seed
<section id='challengeSeed'>

<div id='js-seed'>

```js
function euler248() {
  // Good luck!
  return true;
}

euler248();
```

</div>



</section>

## Solution
<section id='solution'>

```js
// solution required
```
</section>