<p>You are given a positive integer <code>n</code>.</p> <p>Continuously replace <code>n</code> with the sum of its <strong>prime factors</strong>.</p> <ul> <li>Note that if a prime factor divides <code>n</code> multiple times, it should be included in the sum as many times as it divides <code>n</code>.</li> </ul> <p>Return <em>the smallest value </em><code>n</code><em> will take on.</em></p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> n = 15 <strong>Output:</strong> 5 <strong>Explanation:</strong> Initially, n = 15. 15 = 3 * 5, so replace n with 3 + 5 = 8. 8 = 2 * 2 * 2, so replace n with 2 + 2 + 2 = 6. 6 = 2 * 3, so replace n with 2 + 3 = 5. 5 is the smallest value n will take on. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> n = 3 <strong>Output:</strong> 3 <strong>Explanation:</strong> Initially, n = 3. 3 is the smallest value n will take on. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 <= n <= 10<sup>5</sup></code></li> </ul>