if this much salary is enough to manage my living expenses in Sweden

https://www.numbeo.com/cost-of-living/rankings_by_country.jsp

https://www.numbeo.com/cost-of-living/compare_countries.jsp

https://www.routesnorth.com/planning-your-trip/cost-of-living-in-sweden/

Will I be able to save some money?

probably, but that depends on your living expenses and standards. we don't know what they are.

How much can I save (maximum)? 28.6k SEK to 33.5k SEK, minus taxes and inflation.

is a PhD from a Swedish university considered on par with those from US?

on par, how? considered by whom? there are multiple university rating sites and university-specific article rankings to find this out.

how did you get a M.S. in STEM if you're unable to find easily accessible information, do basic calculations, and see that you're looking for answers to questions with hidden variables?