July 1 (Reuters) - American tourists headed for Japan have surged this year, lured by a slump in the value of the yen, which is also driving a massive jump in foreign investor interest in the country's lodgings market.

The number of Americans arriving in Japan by air crossed more than 900,000 in the first five months of 2024, climbing 17.4% year-over-year and vaulting 35.5% from 2019 before the pandemic, the International Trade Administration data showed.

While pent-up travel demand since the end of the pandemic has also contributed, the Japanese currency's recent plunge to a 38-year low to the U.S. dollar has been a key factor, as it boosts the spending power of American tourists.

Since the end of the pandemic, demand has been booming across the Asia-Pacific, drawing in travelers from China, as well as long-haul visitors from North America with more Americans opting to travel internationally.

"The weakened yen compared to the U.S. dollar makes the entire travel experience more affordable for American tourists," said Tim Hentschel, CEO of travel bookings platform HotelPlanner.

Foreign investments in the Japanese hotel industry have also seen a sharp spike.

Cross-border investments in the industry came in at $1.38 billion in the first half of this year, up 19.2% from the same period of 2023, and 176.3% compared to the first half of 2019, according to MSCI data.

Several U.S.-based hotels such as Marriott, Hilton , Hyatt and Choice have been expanding their footprint in Japan by partnering with local real estate and hospitality companies.

"When someone who doesn't know much about Japan visits the country for the first time, they might be more inclined to book with a familiar name," said Wanping Aw, a travel agent in Tokyo.

Short-term rentals giant Airbnb reported a 130% increase in nights booked by American guests in Japan in 2023 from a year earlier.

Airlines are also moving in tandem with this trend, adding more seats between the U.S. and Japan.

Carriers scheduled about 1.5 million seats between the two countries in June, July and August, a 9% increase from a year earlier, according to data in May from online travel agency Hopper.

United Airlines, Delta Air Lines and American Airlines Group have increased scheduled seat capacity between the U.S. and Japan for the summer by 19%, 10% and 7%, respectively, Hopper data showed.

(Reporting by Aishwarya Jain in Bengaluru; Editing by Sriraj Kalluvila)