Which celestial body's length of day is closest to that of Earth? I know the planets Mars and Eris are among bodies that have the most Earth-like mean solar days (about 24.67 and 25.9 hrs). Among moons there is Mimas of Saturn which has one of the most Earth-like days. Uranus and Neptune also have more Earth-like day lengths than many other known planets or moons. However I don't know of a body in the Earth's planetary system that would have a more Earth-like solar day than Mars (other than the Earth of course). Do you know a planet, moon or asteroid that has a daylength closer to that of Earth than Mars' is?
Methone, a tiny moon of Saturn has an orbital period of 1.01 days. This is approximately 24 hrs and 14 minutes. Ref. 1


https://www.windows2universe.org/our_solar_system/moons_table.html