Every number divisible by 9 is divisible by 3. A number is divisible by 9, if the sum is a multiple of 9 or if the sum of its digits is divisible by 9.
In this case:
[tex]\begin{gathered} 46,386 \\ 4+6+3+8+6=27 \\ 27\text{ is divisible by 9} \end{gathered}[/tex]Then, 46,386 is divisible by 9 and by 3 because every number divisible by 9 is divisible by 3.
