There is a company in my area that has recently ceased trading and although they have an answerphone message on the telephone line (presumably from the exchange as there are no business premises) is it possible to buy/rent the number and re direct to me?
There is a service call; 'Caller Redirect'. Basically if a business moves premises out of an Exchange area have have no choice but to change their number they can still keep the old number and when people ring it an automated message tells the caller the new number.
I have never heard of a business who have gone out of business getting Caller Redirect to say they have gone out of business though.
Its quite possible the they simply did a homemove order and now have the line somewhere else connected to an answering machine.
Either way, someone will still be paying for the number so to bluntly answer your question, no you can't rent it.