Williams committed suicide on August 11, 2014. He would have celebrated his 68th birthday on July 21.
"Robin Williams, for me, was by far one the greatest improvisation artistes," Cyrus said.
"Apart from his versatility, what always blew my mind was the way he would bring characters to life. That manic energy and that sharpness of mind will never be seen again. There really was, in my opinion, only one Robin Williams. He lived with the world, with people and carried us through all our trials and troubles," he added.
To this, comedian Sorabh Pant added: "The first international comedian I ever saw was Robin Williams I laughed almost as much as when I saw Johnny Lever. I could not understand 90 per cent of the jokes. His speed was too fast. It was as if he was operating on a different reality from the audience. He was quick, he was likeable, he was energetic, he had more stamina in a one-hour set than I could squeeze into an entire year of stand-up comedy."
Pant says he was amazed when he saw the legend in movies.
"I saw his stand-up comedy before I saw his movies, and when I saw his movies I was amazed by his eyes and his face. That kind face and those caring eyes and then hearing stories about him being as kind as those eyes was amazing. He, along with Johnny Lever, Russell Peters and Jon Stewart, was one of the reasons I wanted to do comedy," he added.
Besides his stand-up comedy, Williams is known for blockbuster hits such as "Aladdin", "Hook", "Mrs. Doubtfire", "Jumanji", "Good Will Hunting" and the "Night at the Museum" franchise.
On the occasion of Williams' birth anniversary, the documentary "Robin Williams: Come Inside My Mind" will air on Star World on Sunday.
( With inputs from IANS )