Who called from 6478460320

Also got a call from this number. Tried to call back, operator advises me that it's for outgoing calls only.

Just got a call from this number. Insisted on talking to my mum and apparently knew a lot about us already. Definitely fishy.

I keep getting calls from random numbers and this was one of them. They know my name, my email and even some financial things. They say I've won trips and that I registered online. So does anyone remember signing up for anything online? Telephone services or shopping sites?? Anything??