2) 9842 · 456 · 4 =

\(9842 \cdot 456 = 9842 \cdot (400 + 50 + 6)\).

\(9842 \cdot 400 = 3936800\), \(9842 \cdot 50 = 492100\), \(9842 \cdot 6 = 59052\).

\(3936800 + 492100 + 59052 = 4477952\).

\(4477952 \cdot 4 = 17911808\).

Ответ: 17911808