What does sexdecillion mean?
A sexdecillion is an extremely large number: in the short scale, the system used for many English-language scientific and financial contexts, it equals 10^51, or one followed by 51 zeros. The same name represents 10^96 in the long scale. The word is mostly mathematical and is generally used to express an order of magnitude rather than an exact count, since even the smallest examples are impractical to comprehend. It belongs to the sequence of large-number names ending in “-illion,” including decillion, undecillion, duodecillion, tredecillion, quattuordecillion, and quindecillion. Because its meaning varies between British and American number-scale traditions, the scientific-notation value is the clearest way to avoid ambiguity.
nounA number equal to one followed by 51 zeros in the short scale, or 10^51. In the long scale, the term denotes 10^96.
- A large number equal to 10^51 in the short scale, or 10^96 in the long scale.
"The estimate is so large that it is expressed in sexdecillions rather than individual units."
"The computational estimate reached a value of several sexdecillions, making the result impossible to represent directly."
"The author described the number of possible combinations as a sexdecillion, emphasizing how impractical exhaustive testing would be."
The plural is used when referring to multiple quantities or values of this magnitude.
"The simulations generated values in the sexdecillions."
Sexdecillion is so large that even its short-scale value, 10^51, has 52 digits including the leading 1.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does sexdecillion come from?
The word combines the Latin numeral element sex-, meaning “six,” with the suffix -illion, used in the names of large numbers. The naming sequence was developed from Latin numerals and the Italian word milione, meaning “million,” and was adopted into English during the modern period as increasingly large number names were standardized. The “sex-” element reflects the coefficient six in the sequence of million-based number names, while the exact numerical value assigned to the term depends on whether the short or long scale is used.
How sexdecillion is actually used
The term is primarily mathematical and is uncommon in ordinary speech. Its value depends on the number scale being used: in the short scale it is 10^51, while in the long scale it is 10^96. When precision matters, writers should state the scale or give the scientific-notation value.
Easily confused with sexdecillion
A septillion is smaller than a sexdecillion in the short scale: it is 10^48, whereas a sexdecillion is 10^51.