\[\boxed{\mathbf{36}.}\]
\[1)\ 831 \cdot 18 + 18 \cdot 169 =\]
\[= (831 + 169) \cdot 18 =\]
\[= 18 \cdot 1000 = 18\ 000\]
\[2)\ 58 \cdot 1024 - 58 \cdot 824 =\]
\[= 58 \cdot (1024 - 824) =\]
\[= 58 \cdot 200 = 11\ 600\]