"Very funny" is "골 때리다"(gol dde ri da) in Korean.
골때리다 (gol dde ri da) is meaning very funny thing, something funny, outrageous, slang to use against to the unlikely event. Use when there is no rambling there is no basis to the story and thoughts.
골 (Col, brain), 때리다 (Terida, I beat).
In words that are similar, 어이 없다 (Oiopuda).