81690045 ÷ 504 
Our goal is to divide 81690045 by 504.

Step 1:
504 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Include the next digit (1) from the dividend after 8, then repeat: 81 / 504

On to step 2:
504 goes into 81 0 times with a remainder of 81.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 81 after subtracting 0 from 81.
Fetch the next digit (6) from the dividend, attach it to 81 and continue: 816 / 504

Let's proceed to step 3:
504 can be fit into 816 1 times, resulting in a remainder of 312.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we subtract 504 from 816, we get 312.
Fetch the next digit (9) from the dividend, attach it to 312 and continue: 3129 / 504

Moving on to step 4:
When dividing 3129 by 504, we get 6 with a remainder of 105.
Put 6 as the next digit of the answer. 
Result so far: 16.0
Subtracting 3024 from 3129 leaves us with 105.
Bring next digit (0) of the dividend behind the 105 and repeat the process: 1050 / 504

Let's proceed to step 5:
504 goes into 1050 2 times with a remainder of 42.
The next digit of our result is 2. 
Result so far: 162.0
Subtracting 1008 from 1050 leaves us with 42.
Take the next digit (0) from the dividend and append it to 42, then repeat: 420 / 504

On to step 6:
If we divide 420 by 504, we get 0 and a remainder of 420.
Use 0 as the next digit of our solution. 
Result so far: 1620.0
Deduct 0 from 420 and we're left with 420.
Take the next digit (4) from the dividend and append it to 420, then repeat: 4204 / 504

Going ahead to step 7:
4204 divided by 504 is 8 with a remainder of 172.
Put 8 as the next digit of the answer. 
Result so far: 16208.0
Deduct 4032 from 4204 and we're left with 172.
Fetch the next digit (5) from the dividend, attach it to 172 and continue: 1725 / 504

Advancing to step 8:
When dividing 1725 by 504, we get 3 with a remainder of 213.
Record the quotient 3 as the next digit in the result. 
Result so far: 162083.0
Deduct 1512 from 1725 and we're left with 213.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2130, and continue the process.

On to step 9:
504 can be fit into 2130 4 times, resulting in a remainder of 114.
The number 4 becomes the next digit in our result. 
Result so far: 162083.4
Subtracting 2016 from 2130 leaves us with 114.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1140, and continue the process.

Step 10:
The number 504 fits into 1140 2 times, leaving a remainder of 132.
Write down 2 as next digit of the result. 
Result so far: 162083.42
Deduct 1008 from 1140 and we're left with 132.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1320, and continue the process.

Let's proceed to step 11:
1320 divided by 504 is 2 with a remainder of 312.
Put 2 as the next digit of the answer. 
Result so far: 162083.422
If we subtract 1008 from 1320, we get 312.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3120, and continue the process.

The quotient of the division is 162083.422, and the remainder is 0.0312.