34-year-old Silva finished his ten-year stint with City this summer and return to Spain with Real Sociedad.
Torres has followed Silva's path from Valencia to the Etihad and hopes to emulate his idol.
"I do have really good memories of watching him when I was young at La Mestalla," he said. "The team they had, with [David] Villa and [Juan] Mata as well, was excellent. They practically won everything.
"I also have a lot of memories about when we waited for the first-team players to come out from the training sessions. We would be waiting for that moment to ask them pictures and signatures. I remember looking for David Silva above the rest.
"It was a huge honour for me when the club told me I could choose the 21 shirt. Just for what it means here. I will try to give my best and be a part of the history of this club.
"Speaking about reaching what David Silva did in Manchester are very strong words, but obviously it's an honour to inherit his number."