Yes rice is perfectly safe to eat after being left out overnight and it will cause no harm to your health.
As long as the rice hasn't grown any mold on it the rice left out overnight is safe to eat although you might want to add some water to the rice and reheat the rice in the microwave to soften it up again as the rice becomes hard when left out overnight.
But rice takes around 2 to 3 days to begin growing mold on it but overnight the rice will be just fine.
Sometimes I make too much rice and don't have enough room in the refrigerator for the leftover rice so I leave it out overnight and then reheat it the next day and it's always been safe.
Just cover the rice up to prevent bugs from getting to it and the rice will be just fine to eat.