how many days does it take for a property to be permanently deleted once you have deleted it from your analytics account?

Answer

After 35 days.

Q:What happens when you delete a property from your analytics account? A:When you delete a property from your analytics account, it moves to the Trash Can and can be restored within 35 days.
Q:After how many days can a property be permanently deleted? A:After 35 days, the property will be permanently deleted and cannot be restored.