Clickbait lede: There's a "city" in China slightly larger than Sweden by area.
Nagqu prefecture-level city: 450,537 kmยฒ
Sweden: 450,295 kmยฒ
It's more a case of unfortunate naming than anything else. China has the concept of "prefecture-level city" that doesn't need to be a contiguous settled area at all, it's just a prefecture (the administrative layer between a province and a county) that has merged its main city into its jurisdiction. The "city" contains districts in the actual city area and counties and county-level cities in the rural area. Almost 90% of China's prefecture-level divisions have this form.