Herman Burton was arrested Tuesday in Center City about a mile from the Omni Hotel, The Philadelphia Inquirer reported.
Police Capt. James Clark said Burton was carrying Patrick Michael Brady's cellphone and credit cards when he was apprehended.
Brady, 49, was a computer specialist at Jefferson University Hospital in Philadelphia and lived in suburban Chester County. He checked into the hotel Friday night, and his body, beaten and strangled, was found the next morning by firefighters.
Burton, 22, was on probation after being convicted of promoting prostitution. Investigators described him as a man who dresses as and identifies himself as a woman.
Clark said Brady apparently admitted Burton to his hotel room.
"The only thing we know is that for whatever reason, there was an extremely physical altercation," he said.