That may be from Google AdSense Phone Verification.
But that could be a personal call as well because you mentioned that someone called from 'receptionist's phone'. God knows...
I had a missed call from Google a day before yesterday while I was sleeping. I called back and it was from Google. I asked them if it is Adwords department but they said No and they were also not able to tell me that who and why someone was trying to call me because it was a common phone.
I do not work for any big company, am freelancer and have Adsense on some of my websites for 2 years now. Never received a call from them. Isn't it strange.
Any one had same experience, please share and if possible, tell me what could be the issue/whatever. Thank you
If it was something important. They will call again.
The only call I've had from Google was a phone verification call. I had placed a website on Google's local businesses street map, it isn't called that but you get the idea, you have the location of your business placed on a street map. It was an automated call, if that helps.