6. (5 points) Teacher Zhang leads the students of Class 6 (1) to plant trees, and the students can be evenly divided into 5 groups. It is known that each teacher and student plants the same number of trees, and they plant a total of 527 trees. Therefore, Class 6 (1) has $\qquad$ students.
【Answer】Solution: $537=31 \times 17$,
The number of students is a multiple of 5, with the last digit being 5 or 0,
The sum of the number of students and teachers has the last digit as 6 or 1,
The total number of students and teachers is 31,
Therefore, the answer is: 30.