What does the 4664 at Nelson Mandelas birthday concert stand for?!

Question: What does the 4664 at Nelson Mandelas birthday concert stand for!?
Answers:

I believe it was his prisoner numberWww@Enter-QA@Com

It was Mandelas prisoner number!.!.!.!.Www@Enter-QA@Com

The answer content post by the user, if contains the copyright content please contact us, we will immediately remove it.