Ōuchiyama Heikichi was a sumo wrestler from Hitachinaka, Ibaraki, Japan. He made his professional debut in 1944, and reached the top makuuchi division in 1949. He reached the second highest rank of ōzeki in 1955, and was a runner-up in two tournaments. He was well known for his extraordinary size – at 2.02 m tall he was the tallest modern era ōzeki until Akebono in 1992. After his retirement in 1959 he worked as a coach at Tokitsukaze stable and Tatsutagawa stable until his death in 1985.

Hitachinaka is a city located in Ibaraki Prefecture, Japan. As of 1 July 2020, the city had an estimated population of 154,663 in 64,900 households and a population density of 1547 persons per km2. The percentage of the population aged over 65 was 26.1%. The total area of the city is 99.96 square kilometres (38.59 sq mi). It is a "hiragana city", the place name is written with the hiragana syllabary and not the traditional kanji.