Scientifically speaking, yes. While I have no personal information on his birth and death, I have cosulted multiple sources, which advise me that he was born in 1889. Therefore, IF Hitler were still alive, he'd be on the threshold of the ripe old age of 122. While I do believe that Hitler, like other evil powers, would probably unfortunately have the ability to live to an old age without illness or violence affecting his life, I feel like even he would not be able to make it to 122.
Additionally, I have no idea if Ava Braun (sp?) and Hitler fulfilled their suicide pact, if he died at the hands of American soldiers, or if he and Elvis had a secret suicide pact, but I do feel quite certain in my assertion that Adolf Hitler is, in fact, dead.