6
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
What value of $k$ makes the positive five-digit integer $k3,\!57k$ divisible by 18?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
6
What value of $k$ makes the positive five-digit integer $k3,\!57k$ divisible by 18?
train