Who was the 21st President?

Chester Alan Arthur (October 5, 1829 – November 18, 1886) was an American politician who served as the twenty-first President of the United States. Arthur was a member of the Republican Party and worked as a lawyer before becoming the 20th vice president under James Garfield. While Garfield was mortally wounded by Charles Guiteau on July 2, 1881, he did not die until September 19, at which time Arthur was sworn in as president, serving until March 4, 1885.