The rice cookers are very good at keeping things at a safe temp. The good ones will have power failure detection.

I regularly make a (work) weeks worth of rice on Sunday night and eat through it until Thursday or Friday or so. Been doing this for well over a decade so far.

The first two days you probably can't tell the difference unless you are a rice snob. After that the taste tends to suffer a bit, but infinitely better than reheating rice from the fridge.