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What Comes After Trillion? Names of Large Numbers


Not sure what number comes after trillion? Interested in the names of other very large numbers? What is a Googol exactly? Read on to learn what comes after trillion, the name of every important number that's larger than trillion, and some ways to help you conceptualize extremely large values.


What Comes After Trillion?

What's after trillion? Trillion is a 1 with 12 zeros after it, and it looks like this: 1,000,000,000,000. The next named number after trillion is quadrillion, which is a 1 with 15 zeros after it: 1,000,000,000,000,000.

There are, of course, many numbers between trillion and quadrillion, but it isn't until quadrillion that that number value actually gets a new name. Numbers between the two would always include the word "trillion": two trillion, a hundred trillion, etc.

As you can see from the chart in the next section, there is a new name every time the power of a large number increases by 3.


Names of Large Numbers

While trillion is an incredibly large number, there are actually many numbers that are larger than it. Below is a chart of all the significant numbers that come after trillion.

The numbers are written with scientific notation to make them easier to read and understand.

Name Number
Million 1 x 10 6
Billion 1 x 10 9
Trillion 1 x 10 12
Quadrillion 1 x 10 15
Quintillion 1 x 10 18
Sextillion 1 x 10 21
Septillion 1 x 10 24
Octillion 1 x 10 27
Nonillion 1 x 10 30
Decillion 1 x 10 33
Undecillion 1 x 10 36
Duodecillion 1 x 10 39
Tredecillion 1 x 10 42
Quattuordecillion 1 x 10 45
Quindecillion 1 x 10 48
Sexdecillion 1 x 10 51
Septendecillion 1 x 10 54
Octodecillion 1 x 10 57
Novemdecillion 1 x 10 60
Vigintillion 1 x 10 63
Unvigintillion 1 x 10 66
Duovigintillion 1 x 10 69
Trevigintillion 1 x 10 72
Quattuorvigintillion 1 x 10 75
Quinvigintillion 1 x 10 78
Sexvigintillion 1 x 10 81
Septenvigintillion 1 x 10 84
Octovigintillion 1 x 10 87
Nonvigintillion 1 x 10 90
Trigintillion 1 x 10 93
Untrigintillion 1 x 10 96
Duotrigintillion 1 x 10 99
Ten-duotrigintillion (or Googol) 1 x 10 100
Skewer's Number 1 x 10 130
Centillion 1 x 10 303
Googolplex 1 x 10 10 100
Skewes' Number skewes number


As you can see, for most of the chart, the power of 10 increases by three for each new number, which means you add three extra zeros to the end of the number to get the next number. For example, a billion is a 1 with nine zeros after it or: 1,000,000,000. Trillion, the next number, is a 1 with twelve zeros after it, or: 1,000,000,000,000.

This pattern continues until you get to Ten-duotrigintillion, more commonly known as a Googol (yes, this is where search engine Google got their name from). There are no names for the numbers between Googol, Skewer's Number, Centillion, or Googolplex.

You may have noticed that "zillion" is not on here. Zillion is not actually a real number; it's simply a term used to refer to an undetermined but extremely large quantity.




Understanding Large Numbers

You can see all the key massive numbers by looking at the chart above, but what do those numbers actually mean, and how can you understand them? It can be difficult, or even impossible, to conceptualize extremely large numbers, but there are some tricks to getting a general idea of just how large they are. Trillion is one of the smallest numbers in the chart, but it's still an incredibly large number. If you were to try to count to trillion, it'd take you roughly 31,709 years to do so!

A googol, or a 1 with one hundred zeros after it, looks like this when written out: 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. Writing a large number out like that can sometimes give a better sense of how big it actually is compared to using scientific notation.

And what about a googolplex, one of the massive numbers in the chart? A googolplex is 1 followed by a googol of zeros. A googolplex is such a large number that there really is no known use for it yet in math, and some mathematicians and astronomers hypothesize that a googolplex is even greater than the number of atoms in the universe.

But, there are numbers even larger than a googolplex. Skewes' number, developed by mathematician Stanley Skewes is 10 to the 10th to the 10th to the 34th. Skewes was particularly interested in prime numbers, and, when his number was introduced in 1933, it was described by a colleague as "largest number which has ever served any definite purpose in mathematics."

However, Skewes' number has since lost that distinction to Graham's number, which is currently designated as the world's largest number. Graham's number, which cannot be written with conventional notation, was developed by mathematician R.L. Graham. It is so large that, even if all the matter in the universe was converted to pens and ink, it still wouldn't be enough to write out the number in its entirety.


Summary: What Comes After Trillion?

What's after trillion? The next number after trillion is quadrillion, or a 1 with 15 zeros after it: 1,000,000,000,000,000. Knowing the names of large numbers can be useful if you're working with extremely large values or doing higher-level mathematics.

Currently, the largest known number is Graham's number, which is too large and complicated to either be written down or conceptualized.


What's Next?

Writing a research paper for school but not sure what to write about? Our guide to research paper topics has over 100 topics in ten categories so you can be sure to find the perfect topic for you.

Learning about natural logs? Check out our guide on the 11 natural log rules you must know to ace this subject.

What is dynamic equilibrium and what does it have to do with rusty cars? Find out by reading our complete guide to dynamic equilibrium.


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Christine Sarikas
About the Author

Christine graduated from Michigan State University with degrees in Environmental Biology and Geography and received her Master's from Duke University. In high school she scored in the 99th percentile on the SAT and was named a National Merit Finalist. She has taught English and biology in several countries.

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