Time actually moves slower at the center of the galaxy due to gravitational forces which have an order of magnitude more impact than the speed difference.

Someone living at the center of the galaxy wouldn't notice of course because the effect is only observable in relativity. 🙃 

 Thanks for the reply 🙂 sure, beings on that planet wouldn't notice. I also don't expect to move to another planet where I can get older in the near future 😄 
Just wondering in general how much of a difference it could make 

 Someone did the math, though with a lot of guessing as we don't know the mass of the milky way:

The center should be ~100,000 years younger over the 13.7 billion years it existed so about 0.0007% in difference.

https://physics.stackexchange.com/a/161482