<p>A <a href="https://en.wikipedia.org/wiki/Perfect_number" target="_blank"><strong>perfect number</strong></a> is a <strong>positive integer</strong> that is equal to the sum of its <strong>positive divisors</strong>, excluding the number itself. A <strong>divisor</strong> of an integer <code>x</code> is an integer that can divide <code>x</code> evenly.</p> <p>Given an integer <code>n</code>, return <code>true</code><em> if </em><code>n</code><em> is a perfect number, otherwise return </em><code>false</code>.</p> <p> </p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> num = 28 <strong>Output:</strong> true <strong>Explanation:</strong> 28 = 1 + 2 + 4 + 7 + 14 1, 2, 4, 7, and 14 are all divisors of 28. </pre> <p><strong>Example 2:</strong></p> <pre> <strong>Input:</strong> num = 7 <strong>Output:</strong> false </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= num <= 10<sup>8</sup></code></li> </ul>