| In words | Prefix (Symbol) | Decimal | Power of ten | Order of Magnitude |
|---|
| nonillionth | quecto- (q) | 0.000000000000000000000000000001 | 10−30 | −30 |
| octillionth | ronto- (r) | 0.000000000000000000000000001 | 10−27 | −27 |
| septillionth | yocto- (y) | 0.000000000000000000000001 | 10−24 | −24 |
| sextillionth | zepto- (z) | 0.000000000000000000001 | 10−21 | −21 |
| quintillionth | atto- (a) | 0.000000000000000001 | 10−18 | −18 |
| quadrillionth | femto- (f) | 0.000000000000001 | 10−15 | −15 |
| trillionth | pico- (p) | 0.000000000001 | 10−12 | −12 |
| billionth | nano- (n) | 0.000000001 | 10−9 | −9 |
| millionth | micro- (µ) | 0.000001 | 10−6 | −6 |
| thousandth | milli- (m) | 0.001 | 10−3 | −3 |
| hundredth | centi- (c) | 0.01 | 10−2 | −2 |
| tenth | deci- (d) | 0.1 | 10−1 | −1 |
| one | | 1 | 100 | 0 |
| ten | deca- (da) | 10 | 101 | 1 |
| hundred | hecto- (h) | 100 | 102 | 2 |
| thousand | kilo- (k) | 1000 | 103 | 3 |
| million | mega- (M) | 1000000 | 106 | 6 |
| billion | giga- (G) | 1000000000 | 109 | 9 |
| trillion | tera- (T) | 1000000000000 | 1012 | 12 |
| quadrillion | peta- (P) | 1000000000000000 | 1015 | 15 |
| quintillion | exa- (E) | 1000000000000000000 | 1018 | 18 |
| sextillion | zetta- (Z) | 1000000000000000000000 | 1021 | 21 |
| septillion | yotta- (Y) | 1000000000000000000000000 | 1024 | 24 |
| octillion | ronna- (R) | 1000000000000000000000000000 | 1027 | 27 |
| nonillion | quetta- (Q) | 1000000000000000000000000000000 | 1030 | 30 |
