updated 06/11/2013 AT 3:00 PM ET
•originally published 06/13/2013 AT 3:30 PM ET
So how does newly-minted octogenarian Joan Rivers – a.k.a. the workhorse comedienne with legendary stamina – keep her eyes on the prize?
Two words: Betty White.
“If that’s 90, where do I sign?” says the Fashion Police host of the 91-year-old actress.
For Rivers – who turned 80 on June 8 and took over the E! channel this week to mark the occasion – White is an inspiration. “I did her show, Hot in Cleveland. She knew all her lines, was running all around. After that, I thought, 80 is nothing!”
“I feel 25 [or] 35,” adds Rivers. “I take the stairs. Everything is working. I perform, make people happy, get a check. What could be nicer?”
Due to the unexpected passing of Rivers’s sister, Barbara Waxler, on June 3, Rivers’s daughter, Melissa, postponed a star-studded surprise fete.