The formula to calculate the maximum frictional force is $$F_{\text{static}} = \mu_s N, \, F_{\text{kinetic}} = \mu_k N$$. Here, $$\mu$$ (pronounced mew) is called the co-efficient of static $$\mu_s$$ or kinetic $$\mu_k$$ friction.
$$\mu$$ is constant for a given surface. The table here lists $$\mu$$'s for a variety of surfaces. You can see that the rougher surfaces have a higher $$\mu$$.