I received a call

I received a call stating that my iCloud had been accessed and hacked. I was told to download a app called any desk and was asked to give them the 9 digit number. I declined because I was uncomfortable with the situation and stated I would hang up and contact apple support directly because of no call ID stating the call came from apple. The lady with an foreign accent became agitated so I just hung up. I would like to know how to find out if my phone has been hacked and what can I do to stop my bank information from being accessed.