## Prefixes

In maths and physics, large and small numbers are common. To aid number economy, prefixes are used to make the job of writing down and remembering large and small numbers easier.
 Prefix Factor Symbol Yotta $10^{24}$ Y Zeta $10^{21}$ Z Exa $10^{18}$ E Peta $10^{15}$ P Tera $10^{12}$ T Giga $10^9$ G Mega $10^6$ M Kilo $10^3$ K Hecto $10^2$ H deca $10$ da deci $10^{-1}$ d centi $10^{-2}$ d milli $10^{-3}$ m micro $10^{-6}$ T nano $10^{-9}$ n pico $10^{-12}$ p femto $10^{-15}$ f atto $10^{-18}$ a zepto $10^{-21}$ z yotto $10^{-24}$ y