# Compute Carmichael function and Euler’s totient function

How can I compute the Carmichael function and Euler’s totient function of 172872 ?

Thank you

• One further difference is that $\phi(2^n)=2^{n-1}$ whereas $\lambda(2^n)=2^{n-2}$ for $n>2$. Jan 5 '14 at 20:50