G4.1 In $P$ be the product of $3,659,893,456,789,325,678$ and $342,973,489,379,256$, find the number of digits of $P$.
$$
\begin{array}{l}
3,659,893,456,789,325,678=3.7 \times 10^{18} \text { (correct to } 2 \text { sig. fig.) } \\
342,973,489,379,256=3.4 \times 10^{14} \text { (correct to } 2 \text { sig. fig.) } \\
P \approx 3.7 \times 10^{18} \times 3.4 \times 10^{14}=12.58 \times 10^{32}=1.258 \times 10^{33}
\end{array}
$$

The number of digits is 34 .