In the solar system, the Milky Way, Mercury is the closest planet to the Sun. Since this planet is the closest, it is bizarre to hear that it rotates so slowly around the sun. It takes almost 88 days to get around the sun. However, it is the shortest orbit time when compared to all the other planets in the system. At one point, scientists believed that this planet rotated synchronously.
This means that one area of the planet always faced the Sun. Since this took place it would cause the planet to actually turn one and a half times for its rotation. This would take a lot long than it really should if it was rotating in the same manner as Earth as the other planets.