The Guinness Book of Records has awarded this rank once to Zied Fazakh who has said that he knows 58 languages. However on a TV show where he was invited, he couldn't answer elementary questions in those languages which he allegedly very well knew.
Other candidate for knowledge of the champion of language skills is the German diplomat Emil Krebs who has died in 1930. Was considered that he knew 65 languages and studied 120 more! Especially he bragged of the ability to tell in 40 different languages "kiss me on a bum". Worthy knowledge for the politician!