A week is doable if you don't have a lot of predators and can keep the door open, otherwise daily door opening. If you get that figured out, then weekly water and feed is easy to establish, can even go longer with trash can/55 gallon drums for feed and water. If you do those, then it's just eggs which you can collect when you're back
Discussion
There's definitely a fox that shows up from time to time in the backyard. That's the only daytime concern. Later night visits from neighborhood cat (maybe a threat to chickens?), skunks (no), opossum (no). Raccoons (?), too, but haven't seen any in a while.
Sounds like for longer trips I'd hopefully recruit a more willing / outdoorsy neighbor for at least a weekly check in and all the free eggs they care to take!