Has the Iphone 6 been copyrighted/trademarked?

Also, how can I see what a company has copyrighted/trademarked?

The word "IPHONE" has been a registered trademark in the USA since 1999, currently owned by Cisco Technologies, for "computer hardware and software for providing integrated telephone communication with computerized global information networks".
http://tsdr.uspto.gov/#caseNumber=75076573&caseType=SERIAL_NO&searchType=statusSearch

There's also an IPHONE registered by a company called "Apple, Inc", since 2009, for various devices and software for hand-held computer services.
http://tsdr.uspto.gov/#caseNumber=77007808&caseType=SERIAL_NO&searchType=statusSearch
There's no "easy" way to find out who has what copyrights or trademarks unless they have filed the optional registations. On the other hand, you can usually tell simply by looking at something whether it is covered by copyright trademark protection. Some people indicate copyright with the optional "copyright notice". Some people indicate trademark with (tm) or service mark (sm) devices associated with the brand.

There's a US Copyright Office that receives requests for registration of copyright ownership for a small fee and issues a certificate for properly filed applications. Anyone can search the online database at copyright.gov. Copyright registration is only required if you're suing someone in US federal court, which has been the rule for over 100 years.

There's a federal trademark office in most countries and, in the USA, a state trademark office in each state, many of which publish online databases of registered trademarks in their respective jurisdictions.