It isn't clear what potential you are talking about.
Mercury is the smallest and the least massive planet, out of the eight in our solar system.
Mercury is the smallest planet in the Solar System
Mercury is the least massive planet in our solar system.
Mercury.
Saturn is the least dense planet in our solar system.
pluto
The planet with the least mass and smallest is Mercury. The planet with the lowest density is Saturn
Saturn is the least dense planet in our solar system.
In our solar system it is Jupiter
All of them are - at least, the planets in the Solar System.
Mercury is the planet in our solar system with the least mass, with a mass of about 0.055 times that of Earth.
Jupiter has at least 79 known moons, making it the planet with the most moons in our solar system.