McCullum has described the former West Indies captain as "the leader of cricket" around the world during his time, reports CMC.
Richards, who has been dubbed by many as the 'most destructive batsman of all time', averages 50.23 with the bat in Tests and 47 in One-Days.
"My favourite West Indies player of all time has to be Sir Viv Richards. He was the leader of cricket right around the world throughout his time; his charisma, the way he carried himself, the way he led his team and obviously the way that he played as well," said McCullum here on Tuesday.
"He wasn't just one of my favourite West Indies players; he was one of my favourite players of all time as well. I had the opportunity to meet him not long ago. Sometimes it's dangerous to meet your heroes, but not on this occasion. It was a really cool moment, and what a guy he is as well."
McCullum is among several international players selected to play in the fourth edition of the Caribbean Premier League (CPL) due to start later this year.
The New Zealand wicketkeeper batsman will represent Trinbago Knight Riders, one of six franchises in the CPL.
"I'm super excited to be featuring in this edition of the 2016 CPL. It's really special to be playing in the Caribbean; the fan engagement and carnival atmosphere is something I've heard a lot from a lot of players around the world," said McCullum, who has gathered 2,140 runs from 71 T20 International matches with a top score of 123.
"My favourite memories of playing in the West Indies are in touring around some of the boutique grounds I've been involved in. I guess there are the cultural aspects of the Caribbean (as well), and just getting to meet some of the great people over there."
McCullum is representing a franchise that also includes South African Hashim Amla, Umar Akmal of Pakistan and former West Indies stroke-maker Ramnaresh Sarwan.