log10(long long) ?

[rodrigorules]

I have a long long type that i am trying to find the log10 of but I can't seem to get around an error..any solutions?

thanks

(n2 is long long)

unsigned long long L2 = log10(n2) /  log10(2);

Error	1	error C2668: 'log10' : ambiguous call to overloaded function	c:\documents and settings\all users\desktop\3216968-src.cpp	14

log10 - C++ Reference

takes double and long double..should I be trying to do a conversion?

(and if it matters, the value i am holding in n2 is slightly under 1million)

thanks