An automated voice claimed it was Home Land Affairs and my identity had been breached. i just hung up. It's interesting to note that I do keep my mobile number very private. However, I did just enter a well know TV channel competition using the '19' number and had registered for a workshop through a very popular events website early today. Is this just a coincidence?
Quora writes area code '642' is "at the moment it’s unallocated. If you did get a call from it, someone is Spoofing the caller ID in order to complete the calls into the telco networks"
Please note that there was no +61 in front of it. It was the only way I could lodge an entry on this phone number.