Happens quite a bit
If it was turned off when it was washed, and you did not turn it back on, there is good chance that drying it in the sun for a few hours will dry it out. If that doesn’t work, the Apple store unless there is a Geek near you. Check the classified.
Put it in a bag of rice for a couple of days. If you have a gas oven with a pilot light, put the bag in the oven to help dry it out. Or use a hot light, sun lamp, what have you, on the bag of rice. The rice is hydrophilic, it’ll draw the water out, the heat will help.