Question

Using divisibility test, determine $639210$ is divisible by $6$.

Answer 1

A number is divisible by 6 if it is divisible by $2$ and $3$ both.
When $639210$ is divided by $2$, we get zero remainder, therefore $639210$ is divisible by $2$.
When $639210$ is divided by $3$, we get remainder zero, therefore $639210$ is divisible by $3$.
Hence, $639210$ is divisible by $6$.