The answer is Uranus. Its farthest distance from the Sun (aphelion) as point of reference is approximately 3 billion kilometers. Whereas Earth's distance from the Sun is about 150 million kilometers. Dividing Earth's distance to sun with the Uranus' distance to the Sun will give us the quotient of 20. Hence, Uranus is the planet that is 20 times farther from the Sun than the Earth is.