Divisibility rules. Game on.

Add the digits: $9 + 9 = 18\textsf{.}$

The last digit of $130$ is $0\textsf{,}$ so $130$ is divisible by $10\textsf{.}$

The last digit of $84$ is $4\textsf{,}$ which is even, so $84$ is divisible by $2\textsf{.}$

The sum of the digits of $27$ is $2 + 7 = 9\textsf{,}$ and $9$ is divisible by $3\textsf{,}$ so $27$ is divisible by $3\textsf{.}$

The last digit of $45$ is $5\textsf{,}$ so $45$ is divisible by $5\textsf{.}$

The sum of the digits of $81$ is $8 + 1 = 9\textsf{,}$ and $9$ is divisible by $9\textsf{,}$ so $81$ is divisible by $9\textsf{.}$

Add the digits: $1 + 1 + 1 = 3\textsf{.}$

The last digit of $20$ is $0\textsf{,}$ so $20$ is divisible by $10\textsf{.}$