What is the greatest common factor of 81 and 52?

To find the greatest common factor (GCF) of 81 and 52, follow these steps:

1. First, find the prime factors of each number.

   For 81, the prime factors are 3 x 3 x 3 x 3.

   For 52, the prime factors are 2 x 2 x 13.

2. Next, identify the common prime factors.

   In this case, there are no common prime factors between 81 and 52.

3. Since there are no common prime factors, the greatest common factor of 81 and 52 is 1.