23891674 ÷ 646 
We want to figure out the number of times 23891674 can be divided by 646.

Step 1:
646 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Grab the next digit (3) from the dividend, add it to 2, then carry on: 23 / 646

Step 2:
646 goes into 23 0 times with a remainder of 23.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 23 leaves us with 23.
Take the next digit (8) from the dividend and append it to 23, then repeat: 238 / 646

On to step 3:
646 goes into 238 0 times with a remainder of 238.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 238, we get 238.
Fetch the next digit (9) from the dividend, attach it to 238 and continue: 2389 / 646

Going ahead to step 4:
646 goes into 2389 3 times with a remainder of 451.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
The remainder is 451 after subtracting 1938 from 2389.
Fetch the next digit (1) from the dividend, attach it to 451 and continue: 4511 / 646

Going ahead to step 5:
If we divide 4511 by 646, we get 6 and a remainder of 635.
Write down 6 as next digit of the result. 
Result so far: 36.0
The remainder is 635 after subtracting 3876 from 4511.
Take the next digit (6) from the dividend and append it to 635, then repeat: 6356 / 646

Let's proceed to step 6:
The number 646 fits into 6356 9 times, leaving a remainder of 542.
Use 9 as the next digit of our solution. 
Result so far: 369.0
Subtract 5814 from 6356 to get 542.
Bring next digit (7) of the dividend behind the 542 and repeat the process: 5427 / 646

Step 7:
If we divide 5427 by 646, we get 8 and a remainder of 259.
Record the quotient 8 as the next digit in the result. 
Result so far: 3698.0
The remainder is 259 after subtracting 5168 from 5427.
Fetch the next digit (4) from the dividend, attach it to 259 and continue: 2594 / 646

Let's proceed to step 8:
If we divide 2594 by 646, we get 4 and a remainder of 10.
Record the quotient 4 as the next digit in the result. 
Result so far: 36984.0
Deduct 2584 from 2594 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 9:
646 goes into 100 0 times with a remainder of 100.
The next digit of our result is 0. 
Result so far: 36984.0
Subtracting 0 from 100 leaves us with 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

On to step 10:
1000 divided by 646 is 1 with a remainder of 354.
The next digit of our result is 1. 
Result so far: 36984.01
The remainder is 354 after subtracting 646 from 1000.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3540, and continue the process.

Advancing to step 11:
646 can be fit into 3540 5 times, resulting in a remainder of 310.
Put 5 as the next digit of the answer. 
Result so far: 36984.015
The remainder is 310 after subtracting 3230 from 3540.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3100, and continue the process.

Going ahead to step 12:
When dividing 3100 by 646, we get 4 with a remainder of 516.
The next digit of our result is 4. 
Result so far: 36984.0154
If we subtract 2584 from 3100, we get 516.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5160, and continue the process.

Advancing to step 13:
The number 646 fits into 5160 7 times, leaving a remainder of 638.
Record the quotient 7 as the next digit in the result. 
Result so far: 36984.01547
If we take 4522 away from 5160, we end up with 638.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6380, and continue the process.

Step 14:
If we divide 6380 by 646, we get 9 and a remainder of 566.
The next digit of our result is 9. 
Result so far: 36984.015479
Subtract 5814 from 6380 to get 566.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5660, and continue the process.

Moving on to step 15:
When dividing 5660 by 646, we get 8 with a remainder of 492.
Write down 8 as next digit of the result. 
Result so far: 36984.0154798
Subtracting 5168 from 5660 leaves us with 492.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4920, and continue the process.

On to step 16:
If we divide 4920 by 646, we get 7 and a remainder of 398.
The next digit of our result is 7. 
Result so far: 36984.01547987
Deduct 4522 from 4920 and we're left with 398.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3980, and continue the process.

The final result is 36984.01547987 with a remainder of 3.98e-07.