1.) Wise/experience - They have been alive for a long time, they have learned so much, and gone through so much. Deaths, new beginnings, bad and good things and define their life.
2.) Determined - Obviously they are determined to live. It's pretty rare to live that long and be very healthy for more years to come.
Here are some things that they probably did to stay as old as they are.
Positive attitude, exercising, living independently, eating good food, and etc...
Hope I helped.