Have you ever wondered how many zeros are in a million? How about a billion? How many zeros in a trillion? Here is a quick list of numbers and how many 0s they have:

Ten: 10 (1 zero)

Hundred: 100 (2 zeros)

Thousand: 1000 (3 zeros)

Ten thousand 10,000 (4 zeros)

Hundred thousand 100,000 (5 zeros)

Million 1,000,000 (6 zeros)

Billion 1,000,000,000 (9 zeros)

Trillion 1,000,000,000,000 (12 zeros)

Quadrillion 1,000,000,000,000,000 (15 zeros)

Quintillion 1,000,000,000,000,000,000 (18 zeros)

Sextillion 1,000,000,000,000,000,000,000 (21 zeros)

Septillion 1,000,000,000,000,000,000,000,000 (24 zeros)

Octillion 1,000,000,000,000,000,000,000,000,000 (27 zeros)

Nonillion 1,000,000,000,000,000,000,000,000,000,000 (30 zeros)

Decillion 1,000,000,000,000,000,000,000,000,000,000,000 (33 zeros)

From there, it gets crazy (although the prefixes for the numbers make sense)...

Name | Number of Zeros |

undecillion | 36 |

duodecillion | 39 |

tredecillion | 42 |

quattuordecillion | 45 |

quindecillion | 48 |

sexdecillion | 51 |

septendecillion | 54 |

octodecillion | 57 |

novemdecillion | 60 |

vigintillion | 63 |

centillion | 100 |

### Zeros Grouped in Sets of Three

Except for the relatively small numbers, names for sets of zeros is reserved for groupings of three zeros. It's the convention to write numbers with commas separating sets of three numbers so that it's easier to read and understand the value. For example, you write one million as 1,000,000 rather than 1000000.

### Numbers With Very Large Numbers of Zeros

The number *googol* (termed by Milton Sirotta) has 100 zeros after it. Milton Sirotta named this wildly big number, which looks like this:

10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

Do you think that number is big? How about the *googolplex*, which is a 1 followed by a googol of zeros. The googolplex is so large it doesn't have any meaningful use yet. The number is larger than the number of atoms in the universe!

### Million and Billion: American vs British

In the United States, as well as around the world in science and finance, a billion is 1,000 million, which is written as a 1 followed by 9 zeros.

This is also called the "short scale".

There is also a "long scale", which is used in France and used to be used in the UK, in which a billion means 1 million million. According to this definition of a billion, the number is written with a 1 followed by 12 zeros. The short scale and long sale were described by French mathematician Genevieve Guitel in 1975.