Metric Numbers
(See also Metric/Imperial Conversion Charts and Unit Conversion Tool)
In the Metric System there are standard ways of talking about big
and small numbers:
- "kilo" for a thousand,
- "mega"
for a million,
- and more ...
Example, if a long rope measures one thousand meters,
it is easier to say it is one kilometer long, and even easier
to write it down as 1 km.
In that example we used kilo in front of the word meter to make "kilometer".
And the abbreviation is "km" (k for kilo and m for meter, put together).
Here are some more examples:
Example 2: if we put something on a set of scales and it shows
2,000 grams, we can call that 2 kilograms, or even 2 kg.
Example 3: If the doctor wants you to take 5 thousandths of a liter of medicine (thousandth=one thousand times smaller),
he is more likely to say "take 5 milliliters",
or write it down as 5mL. "kilo", "mega", "milli" etc are called "prefixes":
Prefix: a word part that can be added to the beginning of another word to create a new word
So, using the prefix "milli" in front of "liter" creates a new word "millilter".
Here we list the prefix for commonly used big and small numbers:
Common Big and Small Numbers
| Name |
The
Number |
Prefix |
Symbol |
| trillion |
1,000,000,000,000 |
tera |
T |
| billion |
1,000,000,000 |
giga |
G |
| million |
1,000,000 |
mega |
M |
| thousand |
1,000 |
kilo |
k |
| hundred |
100 |
hecto |
h |
| ten |
10 |
deka |
da |
| unit |
1 |
|
|
| tenth |
0.1 |
deci |
d |
| hundredth |
0.01 |
centi |
c |
| thousandth |
0.001 |
milli |
m |
| millionth |
0.000 001 |
micro |
µ |
| billionth |
0.000 000 001 |
nano |
n |
| trillionth |
0.000 000 000 001 |
pico |
p |
Some Very Big, and Very Small Numbers
| Name |
The
Number |
Prefix |
Symbol |
|
Very Big ! |
|
|
| septillion |
1,000,000,000,000,000,000,000,000 |
yotta |
Y |
| sextillion |
1,000,000,000,000,000,000,000 |
zetta |
Z |
| quintillion |
1,000,000,000,000,000,000 |
exa |
E |
| quadrillion |
1,000,000,000,000,000 |
peta |
P |
| |
Very Small ! |
|
|
| quadrillionth |
0.000 000 000 000
001 |
femto |
f |
| quintillionth |
0.000 000 000 000
000 001 |
atto |
a |
| sextillionth |
0.000 000 000 000
000 000 001 |
zepto |
z |
| septillionth |
0.000 000 000 000
000 000 000 001 |
yocto |
y |
Try To Do Some Yourself!
- How would you refer to a million liters?
- How about one millionth of a meter?
Advanced Topics!
Using Metric Numbers with "Meters"
Here is an illustration of sizes, from the very small (a Quark) to the very large (the known Universe).
The sizes are in meters using metric numbers (just add the word "meter" after them, so you get "millimeter" etc):
The numbers (like 106) are in scientific notation :
Example: 106 is a 1 followed by 6 zeros: 1,000,000. It is also called a million.
The prefix is mega, so a megameter is a million meters.
Example: 10-9 is a 1 moved nine places the other side of the decimal: 0.000 000 001
It is also called a billionth.
The prefix is nano, so a nanometer is a billionth of a meter.
Looking at the illustration you can see that a person is about 1 meter in size, a mountain is about 103 (one thousand) meters in size, and the Sun is about 109 (one billion) meters in size.
We could also say the Sun is about a "gigameter" in size (it is actually 1.392×109 meters, or 1.392 gigameters, or simply 1.392 Gm in diameter).
You can also use Metric Numbers with other measures like seconds, grams and so on.
All Big Numbers We Know
| Name |
As a Power
of 10 |
As a Decimal |
| Thousand |
103 |
1,000 |
| Million |
106 |
1,000,000 |
| Billion |
109 |
1,000,000,000 |
| Trillion |
1012 |
1,000,000,000,000 |
| Quadrillion |
1015 |
etc ... |
| Quintillion |
1018 |
|
| Sextillion |
1021 |
|
| Septillion |
1024 |
|
| Octillion |
1027 |
|
| Nonillion |
1030 |
|
| Decillion |
1033 |
|
| Undecillion |
1036 |
|
| Duodecillion |
1039 |
|
| Tredecillion |
1042 |
|
| Quattuordecillion |
1045 |
|
| Quindecillion |
1048 |
|
| Sexdecillion |
1051 |
|
| Septemdecillion |
1054 |
|
| Octodecillion |
1057 |
|
| Novemdecillion |
1060 |
|
| Vigintillion |
1063 |
|
All Small Numbers We Know
| Name |
As a Power
of 10 |
As
a Decimal |
| thousandths |
10-3 |
0.001 |
| millionths |
10-6 |
0.000 001 |
| billionths |
10-9 |
0.000 000 001 |
| trillionths |
10-12 |
etc ... |
| quadrillionths |
10-15 |
|
| quintillionths |
10-18 |
|
| sextillionths |
10-21 |
|
| septillionths |
10-24 |
|
| octillionths |
10-27 |
|
| nonillionths |
10-30 |
|
| decillionths |
10-33 |
|
| undecillionths |
10-36 |
|
| duodecillionths |
10-39 |
|
| tredecillionths |
10-42 |
|
| quattuordecillionths |
10-45 |
|
| quindecillionths |
10-48 |
|
| sexdecillionths |
10-51 |
|
| septemdecillionths |
10-54 |
|
| octodecillionths |
10-57 |
|
| novemdecillionths |
10-60 |
|
| vigintillionths |
10-63 |
|
|
Home
