Is Uranus the only planet that rotates on its side?
It is the only such planet in our Solar system.
Uranus has the coldest atmosphere at -224C on average. Something that is unique about Uranus is that it has 22 moons. Also, it rotates on its side instead of upright. There are two odd things about the rotation of Uranus. Firstly it is tilted at 98o or 8o past horizontal (it rotates on its side). It also rotates backwards compared to the other planets except for Venus that also rotates backwards.