BANGKOK — The timing of President Rodrigo Duterte of the Philippines couldn’t be better. Before Donald J. Trump’s election victory, the Philippine leader had already named Mr. Trump’s business partner in Manila as a special envoy to the United States.

Mr. Duterte, whose colorful and unpredictable comments have drawn comparisons to Mr. Trump, late last month named the chairman of Century Properties Group, Jose E. B. Antonio, as an envoy to Washington for trade, investment and economic affairs, Philippine news outlets reported. Word of the appointment became public this week.

Stock in Century Properties rose 20 percent on Wednesday on the Philippine Stock Exchange on the news that Mr. Trump had been elected.

The company is building the Trump Tower at Century City, a $150 million, 57-story apartment building in metropolitan Manila. Mr. Trump has no involvement in the project except to provide his brand name.