90571431 ÷ 139 
We want to divide 90571431 by 139.

Let's proceed to step 1:
139 goes into 9 0 times with a remainder of 9.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 9, we end up with 9.
Bring next digit (0) of the dividend behind the 9 and repeat the process: 90 / 139

Going ahead to step 2:
If we divide 90 by 139, we get 0 and a remainder of 90.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 90 leaves us with 90.
Take the next digit (5) from the dividend and append it to 90, then repeat: 905 / 139

Advancing to step 3:
When dividing 905 by 139, we get 6 with a remainder of 71.
Write down 6 as next digit of the result. 
Result so far: 6.0
If we subtract 834 from 905, we get 71.
Include the next digit (7) from the dividend after 71, then repeat: 717 / 139

Step 4:
If we divide 717 by 139, we get 5 and a remainder of 22.
The number 5 becomes the next digit in our result. 
Result so far: 65.0
The remainder is 22 after subtracting 695 from 717.
Fetch the next digit (1) from the dividend, attach it to 22 and continue: 221 / 139

Moving on to step 5:
221 divided by 139 is 1 with a remainder of 82.
Record the quotient 1 as the next digit in the result. 
Result so far: 651.0
Subtracting 139 from 221 leaves us with 82.
Take the next digit (4) from the dividend and append it to 82, then repeat: 824 / 139

Moving on to step 6:
139 goes into 824 5 times with a remainder of 129.
The next digit of our result is 5. 
Result so far: 6515.0
Subtracting 695 from 824 leaves us with 129.
Take the next digit (3) from the dividend and append it to 129, then repeat: 1293 / 139

Step 7:
1293 divided by 139 is 9 with a remainder of 42.
The number 9 becomes the next digit in our result. 
Result so far: 65159.0
The remainder is 42 after subtracting 1251 from 1293.
Take the next digit (1) from the dividend and append it to 42, then repeat: 421 / 139

Advancing to step 8:
139 can be fit into 421 3 times, resulting in a remainder of 4.
Use 3 as the next digit of our solution. 
Result so far: 651593.0
If we take 417 away from 421, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

On to step 9:
139 goes into 40 0 times with a remainder of 40.
The number 0 becomes the next digit in our result. 
Result so far: 651593.0
If we subtract 0 from 40, we get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 10:
400 divided by 139 is 2 with a remainder of 122.
Use 2 as the next digit of our solution. 
Result so far: 651593.02
The remainder is 122 after subtracting 278 from 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1220, and continue the process.

Step 11:
If we divide 1220 by 139, we get 8 and a remainder of 108.
The number 8 becomes the next digit in our result. 
Result so far: 651593.028
If we take 1112 away from 1220, we end up with 108.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1080, and continue the process.

On to step 12:
139 goes into 1080 7 times with a remainder of 107.
The number 7 becomes the next digit in our result. 
Result so far: 651593.0287
Deduct 973 from 1080 and we're left with 107.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1070, and continue the process.

Let's proceed to step 13:
139 can be fit into 1070 7 times, resulting in a remainder of 97.
The next digit of our result is 7. 
Result so far: 651593.02877
If we subtract 973 from 1070, we get 97.
Since there are no more digits in the dividend, we add a zero to the remainder making it 970, and continue the process.

Our division results in 651593.02877 with a remaining 9.7e-05.