Longest I have left the car without a charger or drive is 2 weeks. It has an immobiliser.
It is a Rover V8 and has an Oddysey battery. It started first time. It usually has the Ctek connected and a run out at 2 weeks max to keep it exercised. Don’t like leaving it longer as things seize up, on the car too! The front brakes have stuck lightly a couple of times but nothing else.

Plus Four MY23 Furka Rouge