Number
Prefix Symbol
Increasing
101 deka- da
102 hecto- h
103 kilo- k
106 mega- M
109 giga- G
1012 tera- T
1015 peta- P
1018 exa- E
1021 zeta- Z
1024 yotta- Y
Decreasing
10-1 deci- d
10-2 centi- c
10-3 milli- m
10-6 micro- u (greek u)
10-9 nano- n
10-12 pico- p
10-15 femto- f
10-18 atto- a
10-21 zepto- z
10-24 yocto- y