If semen on your skin is washed with tap water without soap are there any live sperms on your skin even though the semen is already being washed off?

The Chances of that are highly unlikely. It doesn't take a whole lot to kill a sperm cell. Chances are the majority of the sperm cells died upon contact with the skin and air and the up to about 95% of them had died off after a few moments in the open air. After washing the area with soap and water it is likely that 99.9% of cells have been killed off. Science of life is never guaranteed and what may seem like could never happen can become a possibility in a one off situation. However, chances are that there are no remaining sperm cells alive after the skin has been washed with soap and water.