Xiaoyue wrote a two-digit number 59, and Dongdong wrote a two-digit number 89. They asked Archie to write a one-digit number between 59 and 89 to form a five-digit number 59□89, making the five-digit number The number is divisible by 7, may I ask: What is the number written by Archie?
小悦写了一个两位数59，冬冬写了一个两位数89，他们让阿奇写一个一位数放在59与89之间拼成一个五位数59□89，使得这个五位数能被7整除，请问：阿奇写的数是多少？
<result>6</result>