octillion

n. one followed by 27 zeros (USA & Canada); one followed by 48 zeros

The "standard dictionary numbers" Throughout this article, exponential or scientific notation is used. 106 could also be written as the number 1 followed by six 0s, 1 000 000; 109 could be written as 1 000 000 000; and so on.Names of numbers larger than a quadrillion are almost never used, for reasons discussed further below. It is debatable which of them should be considered real working English vocabulary and which are merely trivia, curiosities, or coinages. The following table lists those names of numbers which are found in many English dictionaries and thus have a special claim to being "real words". The "Traditional British" values shown are unused in American English and are becoming obsolete in British English, but are dominant in many non-English-speaking areas, including continental Europe and Spanish-speaking countries in Latin America; see Long and short scales.
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(n.)
According to the French method of numeration (which method is followed also in the United States) the number expressed by a unit with twenty-seven ciphers annexed. According to the English method, the number expressed by a unit with forty-eight ciphers annexed. See Numeration.
  

   cotillion

octillion /ɔk'tiljən/
danh từ, (toán học) (Anh-Đức) một triệu luỹ thừa 8 (Mỹ-Pháp) một nghìn luỹ thừa 9
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