Inspired by the mind-blowing Charles and Ray Eames’ 1977 video with the same title, I started collecting big numbers.

Here’s a (ever growing and ever tantalizing) list, sorted in ascending order.

Number of bacteria in your large intestine at this very moment: 10⁹ (1 billion)

1 000 000 000

Number of years Earth has existed for: 4.54×10⁹ (4.54 billion)

4 540 000 000

Number of people alive today (29 / 08 / 2010): 6.8×10⁹ (6.8 billion)

6 800 000 000

Number of neurons in human brain: 10¹¹ (one hundred billion)

100 000 000 000

Number of people who have ever lived: 1.1×10¹¹ (110 billion)

110 000 000 000

Number of stars in our galaxy: 3×10¹¹ (300 billion)

300 000 000 000

Number of red blood cells in the human body: 2×10¹³ (20 trillion)

20 000 000 000 000

Number of cells in our body : 10¹⁴ (one hundred trillion)

100 000 000 000 000

Number of meters travelled by light in one year: ~10¹⁶ (9.461×10¹⁵ meters) (10 trillion)

10 000 000 000 000 000

Number of bacteria around the world at one time: 10²⁰ (100 billion billion or 100 quintillion)

100 000 000 000 000 000 000

Number of meters from Earth to Canis Major Dwarf Galaxy (nearest galaxy): 2.364×10²⁰ (236.4 quintillion)

236 400 000 000 000 000 000

Number of stars in the observable universe: 7×10²² (70 sextillion)

70 000 000 000 000 000 000 000

Number of grains of sand on Earth: 1×10²⁰ to 1×10²⁴ (100 billion billion to 1 septillion)

100 000 000 000 000 000 000 to 10 000 000 000 000 000 000 000

Some are approximate figures, intended to give an idea of their grandeur. Sources:

Wolfram Alpha

Richard Dawkins (The Greatest Show on Earth, Pg. 117)

Any breathtaking data you would add to the list? I’d love to hear it!