This week, the British comedian sat down with Matt Lauer on the Today Show to talk about his latest book, Revolution – and during the interview, touched upon his former relationship with the American pop star.
"I really enjoyed it," he said when asked about his 14-month marriage. "Katy Perry is an amazing person."
Russell, 39, then joked about how he coped with the breakdown of their highly-publicised romance.
"What happened was after you get married, like anyone who's been married or come out of a relationship, you obviously have a lot of expectations," he said with a cheeky smile.
"And if those expectations don't work out, then it's probably time to grow a big beard and walk around in pyjamas. That's my advice."
Katy and Russell were married in October 2010 in a traditional Hindu ceremony in Rajasthan, India. But fans were left stunned when Russell filed for divorce shortly after Christmas in 2011.
Katy, 29, has previously admitted she found the split "emotionally traumatic".
"It was the death of a dream," she said. "I was in fairytale land, and the reality of it wasn't so."
Following their divorce, Russell went on to date Jemima Khan – although it is thought their romance finished last month after a year of dating.
Katy started a relationship with John Mayer in 2012, which ended earlier this year. She is now rumoured to be dating DJ Diplo.