Exa-
Exa is a decimal unit prefix in the metric system denoting 1018 or 1000000000000000000. It was added as an SI prefix to the International System of Units (SI) in 1975, and has the unit symbol E.
Exa comes from the Ancient Greek ἕξ, used as a prefix ἑξά-, meaning six (like ), because it is equal to 10006.
Examples:
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