This number keeps calling our office and hanging up. I have no idea what it's about.

I've had calls from this number on my cell, which is also my business number, on 11/5, 11/13, 11/25, 11/26, 12/22, 1/7, and 1/20. On the occasions I've picked up, they have hung up on me. Based on that, I'm 99% certain it's a spam call.