In 50 years of programming I've worked with a few. One characteristic is a deep understanding and command of all that they touch.
For example, I worked with Bill Schelter (GNU Common Lisp). In 1980, prior to the Internet, we were working on a problem (tail recursion). He was using the emacs editor and he found a bug.
Bill stopped what he was doing, fetched the sources for emacs (using ftp), found the source of the bug, fixed it, and sent off a patch. After that he restarted emacs and continued right where he left off. It was a virtuoso performance. It was like watching Victor Borga (https://www.youtube.com/watch?v=dKeqaDSjy98).
I know a guy who plays guitar. He can listen to a performance and repeat it as easily as I can type what I read. He can transpose keys, add riffs, change tuning "on the fly", and even play thru with a broken string, adjusting chords to the new "5 string" form. He also knows guitar characteristics, pedal effects, etc., basically "all things guitar".
Great software engineers I've known seem to have complete command of all of the ideas, tools, and techniques. They understand their tools "all the way down to the metal" and all the way "up to the esthetics". You can see great people in all crafts (like woodworking).
They also write beautiful "crafted" code. I'm keyboarding a FORTRAN punched card deck (for an historical museum). You can see from the code that the author wrote clean, careful, and clear code. You can almost feel how good he was.
Greatness isn't about "team player", "hard working", "good at time estimation", or anything "social". Greatness is a property of the person, a deep love of the craft, and a focus on "doing it right".