Who makes a timer for days?

["Bruce W.1" <sorry@xxxxxxxxxxxxxxxxx>]

I'm looking for a simple appliance timer that would turn something on or
off in increments of days instead of hours.  For instance, it could turn
a light off in 34 days or on a specific date.

A countdown time for a single event would work too, I could set it for
say 865 hours.

Does anyone here know if such a device exists?

Thanks for your help.