title: All factors of a given number
body: <p>For example, I have 4800 and I would like to see all the factors of this number. </p>
  
  <pre><code> # num = the number you want factors of
  
   def factors_of(num)
      (1..num).collect { |n| [n, num/n] if ((num/n) * n) == num}.compact
   end
  </code></pre>
  
  <blockquote>
    <p>divisors_of(4800)
    => [[1, 4800], [2, 2400], [3, 1600], [4, 1200], [5, 960], [6, 800], [8, 600], [10, 480], [12, 400], [15, 320], [16, 300], [20, 240], [24, 200], [25, 192], [30, 160], [32, 150], [40, 120], [48, 100], [50, 96], [60, 80], [64, 75], [75, 64], [80, 60], [96, 50], [100, 48], [120, 40], [150, 32], [160, 30], [192, 25], [200, 24], [240, 20], [300, 16], [320, 15], [400, 12], [480, 10], [600, 8], [800, 6], [960, 5], [1200, 4], [1600, 3], [2400, 2], [4800, 1]]</p>
    
    <blockquote>
      <p></p>
    </blockquote>
  </blockquote>
  
  <p>How would you do this in ruby or any language?</p>