641963 divided by 16 
Let's see how many times 16 fits into 641963.

Advancing to step 1:
6 divided by 16 is 0 with a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Take the next digit (4) from the dividend and append it to 6, then repeat: 64 / 16

Let's proceed to step 2:
64 divided by 16 is 4 with a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 4.0
If we subtract 64 from 64, we get 0.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 16

On to step 3:
The number 16 fits into 1 0 times, leaving a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 40.0
Deduct 0 from 1 and we're left with 1.
Include the next digit (9) from the dividend after 1, then repeat: 19 / 16

Moving on to step 4:
When dividing 19 by 16, we get 1 with a remainder of 3.
Record the quotient 1 as the next digit in the result. 
Result so far: 401.0
Deduct 16 from 19 and we're left with 3.
Grab the next digit (6) from the dividend, add it to 3, then carry on: 36 / 16

On to step 5:
16 can be fit into 36 2 times, resulting in a remainder of 4.
Record the quotient 2 as the next digit in the result. 
Result so far: 4012.0
The remainder is 4 after subtracting 32 from 36.
Include the next digit (3) from the dividend after 4, then repeat: 43 / 16

Step 6:
43 divided by 16 is 2 with a remainder of 11.
Write down 2 as next digit of the result. 
Result so far: 40122.0
The remainder is 11 after subtracting 32 from 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 7:
110 divided by 16 is 6 with a remainder of 14.
The next digit of our result is 6. 
Result so far: 40122.6
If we subtract 96 from 110, we get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 8:
If we divide 140 by 16, we get 8 and a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 40122.68
Deduct 128 from 140 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 9:
120 divided by 16 is 7 with a remainder of 8.
Put 7 as the next digit of the answer. 
Result so far: 40122.687
If we take 112 away from 120, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 10:
When dividing 80 by 16, we get 5 with a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 40122.6875
Subtracting 80 from 80 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 11:
0 divided by 16 is 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 40122.6875
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 12:
16 can be fit into 0 0 times, resulting in a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 40122.6875
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 40122.6875, with a leftover of 0.0.