At least 60 for all Hilton Properties:

Notable Ones:

USA
Anchorage: 1
Seattle: 2
San Francisco: 1
Salt Lake City: 1
Denver: 1
Chicago: 1
Hawaii: 3 (Oahu, Maui (Grand Wailea), Waikoloa)


Europe:
Reykjavik (2)
Amsterdam: (1)
The Hague: (1)
Frankfurt: (1)

Africa:
Nairobi

Oceania:
Sydney
Auckland
Christchurch

plus probably 40+ Hilton Garden, Homewood Suites, Double Tree. etc. properties. scattered throughout the world)