Unit prefixes

SI and metric

Symbol Multiple Prefix
µ 10-6 micro-
m 10-3 milli-
c 10-2 centi-
k 103 kilo-
M 106 mega-
G 109 giga-
T 1012 tera-

Customary

Symbol Multiple Prefix
M 103 thousand
MM 106 million
B 109 billion
T 1012 trillion