What numbers should be put behind the phone number if your calling from michigan to south africa?

Hi and thx for taking the time to read and if u do answer this i need help im going on vacation for a month or 2 to michigan in america nad would like to keep in contact with my girlfreind and i would like to know if i will have put any numbers in before i put in her number so for an example im just going to put in my number (071 264 0054) if u answer plz show me and thx again i really appreciate it