---
id: 5900f36f1000cf542c50fe82
challengeType: 5
title: 'Problem 3: Largest prime factor'
videoUrl: ''
localeTitle: ''
---

## Description
undefined

## Instructions
undefined

## Tests
<section id='tests'>

```yml
tests:
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(2), 2, "<code>largestPrimeFactor(2)</code> should return 2.");'
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(3), 3, "<code>largestPrimeFactor(3)</code> should return 3.");'
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(5), 5, "<code>largestPrimeFactor(5)</code> should return 5.");'
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(7), 7, "<code>largestPrimeFactor(7)</code> should return 7.");'
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(13195), 29, "<code>largestPrimeFactor(13195)</code> should return 29.");'
  - text: ''
    testString: 'assert.strictEqual(largestPrimeFactor(600851475143), 6857, "<code>largestPrimeFactor(600851475143)</code> should return 6857.");'

```

</section>

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

<div id='js-seed'>

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

largestPrimeFactor(13195);

```

</div>



</section>

## Solution
<section id='solution'>

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