Yep, Atlas Air does have B777F planes in their fleet.

The 777 Freighter (777F) (unofficially referred to as 777-200LRF by some cargo airlines)[201] is an all-cargo version of the twinjet, and shares features with the -200LR; these include its airframe, engines,[202] and fuel capacity.[148] With a maximum payload of 228,700 lb (103,700 kg) (similar to the 243,000 lb (110,000 kg) of the Boeing 747-200F), it has a maximum range of 9,750 nmi (18,057 km; 11,220 mi)) or 4,970 nmi (9,200 km; 5,720 mi)) at its max structural payload.[203][204][201]

The 777F also features a new supernumerary area, which includes four business-class seats forward of the rigid cargo barrier, full main deck access, bunks, and a galley.[205] As the aircraft promises improved operating economics compared to older freighters,[81] airlines have viewed the 777F as a replacement for freighters such as the Boeing 747-200F, McDonnell Douglas DC-10, and McDonnell Douglas MD-11F.[113][206]

The first 777F was delivered to Air France on February 19, 2009.[116] As of April 2021, 247 freighters have been ordered by 25 different customers with 45 unfilled orders.[2] Operators had 202 of the 777F in service as of 2018.[183]