MOSCOW — He has ridden shirtless on a horse in Siberia, piloted a hang glider with migratory birds, swum with dolphins, tossed judo opponents, and dived into the depths of Lake Baikal and the Black Sea.

He is Russia’s president, Vladimir V. Putin, and he added to his public repertoire of feats on Sunday by showing off his skills as a pianist.

He was in Beijing for the “One Belt, One Road” initiative, a $1 trillion plan for infrastructure and economic development in some 60 countries. And while waiting at a state guesthouse for China’s president, Xi Jinping, Mr. Putin sat down at a grand piano and played two tunes: “Evening Song,” by Vasily Solovyov-Sedoi, and “Moscow Windows,” by Tikhon Khrennikov.