5. (5 points) Decompose a natural number into prime factors. If the sum of the digits of all prime factors equals the sum of the digits of the original number, then such a number is called a "Smith number." For example, $27=3 \times 3 \times 3.3+3+3=2+7$, so 27 is a Smith number. Therefore, among $4,32,58,65,94$, the number of Smith numbers is $\qquad$.

【Solution】Solution: $4=2 \times 2$,
$$
2+2=4,
$$

so 4 is a Smith number;
$$
32=2 \times 2 \times 2 \times 2 \times 2 \text {; }
$$
$2+2+2+2+2=10$, while $3+2=5$;
$10 \neq 5,32$ is not a Smith number;
$$
\begin{array}{l}
58=2 \times 29, \\
2+2+9=13=13 ;
\end{array}
$$

so 58 is a Smith number;
$$
\begin{array}{c}
65=5 \times 13 \\
5+1+3=9 \\
6+5=11
\end{array}
$$
$9 \neq 11,65$ is not a Smith number;
$$
\begin{array}{l}
94=2 \times 47 \\
2+4+7=13=9+4 ;
\end{array}
$$

so 94 is a Smith number.
The Smith numbers are $4,58,94$, a total of 3. The answer is: 3.