What was Agent 99's (Barbara Feldon's) name on the TV series "Get Smart" (NBC, CBS, 1965-70)?

Agent 99’s (Barbara Feldon’s) name on the TV series “Get Smart” was never revealed, although on one episode she had the cover name of Susan Hilton.

Who played Hymie the Robot on the TV series "Get Smart" (NBC, CBS, 1965-70)? Dick Gautier played Hymie the Robot on "Get Smart" (NBC,…
Who played the Chief in The Nude Bomb (1980), the movie based on "Get Smart" (NBC, 1965-70)? Edward Platt did not play the Chief in The Nude…
What were the first names of the shipwrecked Robinsons in the TV series "Lost in Space" (CBS, 1965-68)? Will Robinson (Billy Mumy) is easy to remember from the…
Who were Arnold Ziffel's parents on the TV series "Green Acres" (CBS, 1965-71)? Arnold Ziffel's parents on the TV series "Green Acres" (CBS,…
What was the stalag number on the TV series "Hogan's Heroes" (CBS, 1965-71)? Stalag 13. The PT boat number on "McHale's Navy" (ABC…
Was the author of the James Bond novels ever an agent himself? Yes. Ian Fleming (1908-1964), the author of the James Bond…

What was Agent 99’s (Barbara Feldon’s) name on the TV series “Get Smart” (NBC, CBS, 1965-70)?