If the PC hard drive is dead and the phone is stolen, the picture may still be in your One-Drive cloud storage. When you initialize a Windows phone it asks for your Microsoft account credentials OR lets you create a new Microsoft account. That account comes with cloud storage on One Drive. Unless you turned it off, the phone should automatically back up pictures taken to One Drive when you have WiFi.
From there you will be able to download backed up pictures.
Knowing the phone number won't help unless you still "own" the number and it is assigned to another phone you have because the number would only matter for two factor authentication. If two factor authentication is needed, you would need a phone with that number OR access to the email account you associated with your Microsoft account.