As adults, we understand that there is no such number – we can always add “one” to any monstrously large number to make it even larger. We can create a number with an endless row of zeros to satisfy our curiosity but, frankly speaking, it’s a waste of time. Numbers should mean something and possess practical utility; in other words, they should be invented to quantify something.

## It’s important to know

When it comes to monstrously large numbers, scientists traditionally use approximation. For example, it is believed that there are 10^{21} (1 followed by 21 zeros) stars in the observable universe. It’s only natural that these calculations are approximate. In fact, the exact number of stars can be 1,564,861,615,140,168,357,973 or even 9,999,999,999,999,999,999,999 – for scientists, it’s more important to determine of how many digits this number consists rather than to specify the very digits. By the way, 10^{21} is called a sextillion.

## Large, and larger

You can hardly find a person who doesn’t know that 10^{3} is a thousand, 10^{6} is a million, or 10^{9} is a billion - let’s explore larger numbers:

- 10
^{11}, one hundred billion, is the number of people who have ever lived on Earth; - 10
^{12}, or a trillion, - a trillion seconds ago, mammoths were still alive; - 10
^{15}, or a quadrillion, is the approximate number of ants on Earth; - 10
^{24}, or a septillion, - 1024 kg is the mass of Earth; - 10
^{26}m is the diameter of the observable universe; - 10
^{51}, or a sexdecillion, is the number of atoms our planet composed of;

- There are 10
^{80}elementary particles in the observed universe; - 10
^{100}, or a googol, is just a round number; - There are 10
^{185}Planck volumes – a Planck volume is a unit of length that can be approximated to 10^{-35}m – in the observable universe. Since the Planck volume is the smallest unit of length, 10^{185}is the largest number used for quantitation. - There are numbers larger than 10
^{185}– Graham’s number is so unimaginably large that its digital representation won’t fit in the observable universe, even if each digit will occupy one Planck volume.