NEW YORK - Actors Sean Penn and Stephen Fry, novelist Salman Rushdie and dozens of other friends paid tribute to Christopher Hitchens on Friday in a New York memorial service held four months after his death.

Vanity Fair magazine, for which the British-born journalist worked, said that popular songs of the 1960s and 1970s including "Both Sides Now" and "Like a Rolling Stone" were played at the service in the Great Hall of Cooper Union. A video of clips highlighting his brash style and wit was also played.

Hitchens, an atheist and intellectual, wrote 25 books and numerous articles and columns. He died in December at the age of 62 after a long and public battle with esophageal cancer.

"He was an editor's dream, and he was a reader's dream," Vanity Fair editor Graydon Carter said.

Fry remarked that "one of the great pleasures of knowing Christopher was having him disagree with you." Francis Collins, a friend and the director of the U.S. National Institutes of Health, addressed Hitchen's well-known atheism, which was unshaken by his terminal cancer.

"No doubt he now knows the answer to whether there is more to the spirit than nucleotides and neurotransmitters," Collins said.

Others at the memorial included British authors Ian McEwan and Martin Amis, playwright Tom Stoppard, US journalist Carl Bernstein, actress Olivia Wilde, physicist Lawrence Krauss and Hitchen's wife Carol Blue, Vanity Fair said.