Wanting to switch from US Cellular

Hello, my contract is up in 2 months and I'm planning to switch at that time. From what I understand, my USCellular phone won't be compatible even if it's unlocked (bummer).

Does anyone know if this phone would be compatible?

Also, am I able to keep my number? It was originally an AT&T number which I transferred to USCellular. I've had the same number for over 15 years so I'd hate to change it unless I have to.

Thanks in advance!