The Uncommon Factor Number
05AB1E, 6 bytes

Code

Â‚D¿÷P


Uses the 05AB1E encoding. Try it online!

Explanation

Â‚        # Get the array [input, reversed(input)]
  D       # Duplicate that array
   ¿      # Calculate the GCD of the array
    ÷     # Divide each element in the array by the GCD
     P    # Product of that array