gengan tonaki (渡名喜元完; "tonaki gengan", 30 october 1884 – 24 january 1997) was a japanese (okinawan) farmer and supercentenarian, and at the time of his death at age 112 years, 86 days the oldest japanese man ever (although the claimed 120-year-old shigechiyo izumi was believed to have been older) before being beaten by denzo ishizaki.