521580 divided by 5 
The aim is to understand the frequency of 5 in 521580.

Going ahead to step 1:
The number 5 fits into 5 1 times, leaving a remainder of 0.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we take 5 away from 5, we end up with 0.
Take the next digit (2) from the dividend and append it to 0, then repeat: 2 / 5

Let's proceed to step 2:
2 divided by 5 is 0 with a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 10.0
If we subtract 0 from 2, we get 2.
Fetch the next digit (1) from the dividend, attach it to 2 and continue: 21 / 5

Going ahead to step 3:
If we divide 21 by 5, we get 4 and a remainder of 1.
The next digit of our result is 4. 
Result so far: 104.0
If we subtract 20 from 21, we get 1.
Bring next digit (5) of the dividend behind the 1 and repeat the process: 15 / 5

Advancing to step 4:
When dividing 15 by 5, we get 3 with a remainder of 0.
The number 3 becomes the next digit in our result. 
Result so far: 1043.0
If we subtract 15 from 15, we get 0.
Fetch the next digit (8) from the dividend, attach it to 0 and continue: 8 / 5

Moving on to step 5:
5 goes into 8 1 times with a remainder of 3.
The next digit of our result is 1. 
Result so far: 10431.0
If we take 5 away from 8, we end up with 3.
Fetch the next digit (0) from the dividend, attach it to 3 and continue: 30 / 5

Going ahead to step 6:
5 goes into 30 6 times with a remainder of 0.
The number 6 becomes the next digit in our result. 
Result so far: 104316.0
If we subtract 30 from 30, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 7:
When dividing 0 by 5, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 104316.0
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
The number 5 fits into 0 0 times, leaving a remainder of 0.
The next digit of our result is 0. 
Result so far: 104316.0
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 104316.0, with a leftover of 0.0.