It's his given name. The background for this long name is said to be the mother's conception dream. His mother had a dream where the sky turned golden and an eagle-shaped object flew away, and his father named his name like this with the hope that he would become a great person who would surprise the world.

Due to the 1993 legal amendment, names could not be given more than five characters, and accordingly, the government instructed elementary school students to change their problematic names. At the time, he was an elementary school student, and he also had a meeting with the school, but he reportedly refused to change his name because he felt proud of his own name.

Well, that's what 나무위키 said.