    # File lib/vmail/imap_client.rb, line 277
        def number_to_human_size(number)
          if number.to_i < 1024
            "<1kb" # round up to 1kh
          else
            max_exp = UNITS.size - 1
            exponent = (Math.log(number) / Math.log(1024)).to_i # Convert to base 1024
            exponent = max_exp if exponent > max_exp # we need this to avoid overflow for the highest unit
            number  /= 1024 ** exponent
            unit = UNITS[exponent]
            "#{number}#{unit}"
          end
        end