In[1]:= N[1/3] Out[1]= 0.333333
In[1]:= N[Sqrt[3]] Out[1]= 1.73205
In[1]:= N[Sqrt[3],20] Out[1]= 1.7320508075688772935
In[1]:= 34! Out[1]= 295232799039604140847618609643520000000