1000000000 (number)

1000000000 was a number.

During his ordeal in the confession dial, two successive copies of the Twelfth Doctor respectively believed that they had travelled "nearly a billion" and "well over a billion" years into the future. (TV: Heaven Sent)

By the 1970s, the Nestene Consciousness had been colonising planets for "a thousand million years." (TV: Spearhead from Space)

At the time of its disappearance, Bandraginus V had a population of "a thousand million." (TV: The Pirate Planet)

In 2157, the colony on Sifranos had a billion settlers, all of whom were massacred by the Daleks. (PROSE: Lucifer Rising)

Multiple billions
According to legend, the Face of Boe had lived for billions of years. (TV: Gridlock)