SI prefixes
Name Symbol Multiplying factor Base-10 notation Power-of-ten name
1 quetta Q 1030 1 000 000 000 000 000 000 000 000 000 000 nonillion
2 ronna R 1027 1 000 000 000 000 000 000 000 000 000 octillion
3 yotta Y 1024 1 000 000 000 000 000 000 000 000 septillion
4 zetta Z 1021 1 000 000 000 000 000 000 000 sextillion
5 exa E 1018 1 000 000 000 000 000 000 quintillion
6 peta P 1015 1 000 000 000 000 000 quadrillion
7 tera T 1012 1 000 000 000 000 trillion
8 giga G 109 1 000 000 000 billion
9 mega M 106 1 000 000 million
10 kilo k 103 1 000 thousand
11 hecto h 102 100 hundred
12 deca da 101 10 ten
100 1 one
13 deci d 10−1 0.1 tenth
14 centi c 10−2 0.01 hundredth
15 milli m 10−3 0.001 thousandth
16 micro µ 10−6 0.000 001 millionth
17 nano n 10−9 0.000 000 001 billionth
18 pico p 10−12 0.000 000 000 001 trillionth
19 femto f 10−15 0.000 000 000 000 001 quadrillionth
20 atto a 10−18 0.000 000 000 000 000 001 quintillionth
21 zepto z 10−21 0.000 000 000 000 000 000 001 sextillionth
22 yocto y 10−24 0.000 000 000 000 000 000 000 001 septillionth
23 ronto r 10−27 0.000 000 000 000 000 000 000 000 001 octillionth
24 quecto q 10−30 0.000 000 000 000 000 000 000 000 000 001 nonillionth

Sources


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