16391729 ÷ 90 
Our goal is to divide 16391729 by 90.

Step 1:
1 divided by 90 is 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Append the next digit (6) from the dividend to 1 and continue with: 16 / 90

Moving on to step 2:
16 divided by 90 is 0 with a remainder of 16.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 16 and we're left with 16.
Take the next digit (3) from the dividend and append it to 16, then repeat: 163 / 90

On to step 3:
90 can be fit into 163 1 times, resulting in a remainder of 73.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtracting 90 from 163 leaves us with 73.
Include the next digit (9) from the dividend after 73, then repeat: 739 / 90

Going ahead to step 4:
90 goes into 739 8 times with a remainder of 19.
The number 8 becomes the next digit in our result. 
Result so far: 18.0
Subtracting 720 from 739 leaves us with 19.
Take the next digit (1) from the dividend and append it to 19, then repeat: 191 / 90

Step 5:
90 goes into 191 2 times with a remainder of 11.
The next digit of our result is 2. 
Result so far: 182.0
If we subtract 180 from 191, we get 11.
Fetch the next digit (7) from the dividend, attach it to 11 and continue: 117 / 90

Step 6:
The number 90 fits into 117 1 times, leaving a remainder of 27.
Put 1 as the next digit of the answer. 
Result so far: 1821.0
If we take 90 away from 117, we end up with 27.
Include the next digit (2) from the dividend after 27, then repeat: 272 / 90

Going ahead to step 7:
If we divide 272 by 90, we get 3 and a remainder of 2.
Write down 3 as next digit of the result. 
Result so far: 18213.0
If we take 270 away from 272, we end up with 2.
Fetch the next digit (9) from the dividend, attach it to 2 and continue: 29 / 90

Advancing to step 8:
When dividing 29 by 90, we get 0 with a remainder of 29.
Put 0 as the next digit of the answer. 
Result so far: 182130.0
If we take 0 away from 29, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Let's proceed to step 9:
The number 90 fits into 290 3 times, leaving a remainder of 20.
Write down 3 as next digit of the result. 
Result so far: 182130.3
Subtract 270 from 290 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 10:
If we divide 200 by 90, we get 2 and a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 182130.32
The remainder is 20 after subtracting 180 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 11:
The number 90 fits into 200 2 times, leaving a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 182130.322
Deduct 180 from 200 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

After the division, we end up with 182130.322 and a remainder of 0.002.