Why is a function not an object?

I read in the standards n4296 (Draft) § 1.8 page 7:

An object is a region of storage. [ Note: A function is not an object, regardless of whether or not it occupies storage in the way that objects do. —end note ]

I spent some days on the net looking for a good reason for such exclusion, with no luck. Maybe because I do not fully understand objects. So:

1. Why is a function not an object? How does it differ?
2. And does this have any relation with the functors (function objects)?