We divide 81015063 by 641
The aim is to understand the frequency of 641 in 81015063.

On to step 1:
When dividing 8 by 641, we get 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 641

Let's proceed to step 2:
When dividing 81 by 641, we get 0 with a remainder of 81.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 81 after subtracting 0 from 81.
Grab the next digit (0) from the dividend, add it to 81, then carry on: 810 / 641

Advancing to step 3:
641 goes into 810 1 times with a remainder of 169.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 641 from 810 to get 169.
Fetch the next digit (1) from the dividend, attach it to 169 and continue: 1691 / 641

Let's proceed to step 4:
If we divide 1691 by 641, we get 2 and a remainder of 409.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
Subtracting 1282 from 1691 leaves us with 409.
Append the next digit (5) from the dividend to 409 and continue with: 4095 / 641

Going ahead to step 5:
If we divide 4095 by 641, we get 6 and a remainder of 249.
Use 6 as the next digit of our solution. 
Result so far: 126.0
If we take 3846 away from 4095, we end up with 249.
Bring next digit (0) of the dividend behind the 249 and repeat the process: 2490 / 641

Advancing to step 6:
2490 divided by 641 is 3 with a remainder of 567.
Use 3 as the next digit of our solution. 
Result so far: 1263.0
If we subtract 1923 from 2490, we get 567.
Append the next digit (6) from the dividend to 567 and continue with: 5676 / 641

Advancing to step 7:
641 goes into 5676 8 times with a remainder of 548.
Record the quotient 8 as the next digit in the result. 
Result so far: 12638.0
Subtracting 5128 from 5676 leaves us with 548.
Take the next digit (3) from the dividend and append it to 548, then repeat: 5483 / 641

Advancing to step 8:
641 can be fit into 5483 8 times, resulting in a remainder of 355.
The number 8 becomes the next digit in our result. 
Result so far: 126388.0
Subtracting 5128 from 5483 leaves us with 355.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3550, and continue the process.

On to step 9:
3550 divided by 641 is 5 with a remainder of 345.
The number 5 becomes the next digit in our result. 
Result so far: 126388.5
Deduct 3205 from 3550 and we're left with 345.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3450, and continue the process.

Going ahead to step 10:
If we divide 3450 by 641, we get 5 and a remainder of 245.
Use 5 as the next digit of our solution. 
Result so far: 126388.55
Deduct 3205 from 3450 and we're left with 245.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2450, and continue the process.

The quotient of the division is 126388.55, and the remainder is 0.245.