Sam2: Thanks for explaining it. Noach did not have children until he was 500 years old, and assuming that Na’amah was his wife, she was well over 500 years old as she was born well before Noach.
As for who is the longest living person? The answer is Chirum Melech Tzur, who was rewarded by Hashem for having assisted Shlomo in building the Bais Hamikdash. He lived for a 1000 years and became so conceited that he believed himself to be a deity. For that, Hashem killed him.