87890064 ÷ 399 
Let's see how many times 399 fits into 87890064.

Moving on to step 1:
399 goes into 8 0 times with a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Bring next digit (7) of the dividend behind the 8 and repeat the process: 87 / 399

On to step 2:
399 can be fit into 87 0 times, resulting in a remainder of 87.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 87 to get 87.
Grab the next digit (8) from the dividend, add it to 87, then carry on: 878 / 399

Step 3:
399 can be fit into 878 2 times, resulting in a remainder of 80.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Deduct 798 from 878 and we're left with 80.
Bring next digit (9) of the dividend behind the 80 and repeat the process: 809 / 399

Step 4:
399 can be fit into 809 2 times, resulting in a remainder of 11.
Write down 2 as next digit of the result. 
Result so far: 22.0
If we take 798 away from 809, we end up with 11.
Grab the next digit (0) from the dividend, add it to 11, then carry on: 110 / 399

Moving on to step 5:
If we divide 110 by 399, we get 0 and a remainder of 110.
Write down 0 as next digit of the result. 
Result so far: 220.0
If we subtract 0 from 110, we get 110.
Include the next digit (0) from the dividend after 110, then repeat: 1100 / 399

Advancing to step 6:
The number 399 fits into 1100 2 times, leaving a remainder of 302.
Use 2 as the next digit of our solution. 
Result so far: 2202.0
Subtracting 798 from 1100 leaves us with 302.
Take the next digit (6) from the dividend and append it to 302, then repeat: 3026 / 399

Going ahead to step 7:
When dividing 3026 by 399, we get 7 with a remainder of 233.
Put 7 as the next digit of the answer. 
Result so far: 22027.0
Subtract 2793 from 3026 to get 233.
Bring next digit (4) of the dividend behind the 233 and repeat the process: 2334 / 399

Let's proceed to step 8:
The number 399 fits into 2334 5 times, leaving a remainder of 339.
Write down 5 as next digit of the result. 
Result so far: 220275.0
Subtract 1995 from 2334 to get 339.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3390, and continue the process.

Moving on to step 9:
399 can be fit into 3390 8 times, resulting in a remainder of 198.
Record the quotient 8 as the next digit in the result. 
Result so far: 220275.8
Deduct 3192 from 3390 and we're left with 198.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1980, and continue the process.

Moving on to step 10:
The number 399 fits into 1980 4 times, leaving a remainder of 384.
Write down 4 as next digit of the result. 
Result so far: 220275.84
If we take 1596 away from 1980, we end up with 384.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3840, and continue the process.

Step 11:
399 goes into 3840 9 times with a remainder of 249.
Put 9 as the next digit of the answer. 
Result so far: 220275.849
The remainder is 249 after subtracting 3591 from 3840.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2490, and continue the process.

Advancing to step 12:
399 can be fit into 2490 6 times, resulting in a remainder of 96.
Use 6 as the next digit of our solution. 
Result so far: 220275.8496
If we subtract 2394 from 2490, we get 96.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

Moving on to step 13:
If we divide 960 by 399, we get 2 and a remainder of 162.
Write down 2 as next digit of the result. 
Result so far: 220275.84962
Subtract 798 from 960 to get 162.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1620, and continue the process.

Let's proceed to step 14:
399 goes into 1620 4 times with a remainder of 24.
The next digit of our result is 4. 
Result so far: 220275.849624
If we subtract 1596 from 1620, we get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

On to step 15:
240 divided by 399 is 0 with a remainder of 240.
Record the quotient 0 as the next digit in the result. 
Result so far: 220275.849624
The remainder is 240 after subtracting 0 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Going ahead to step 16:
When dividing 2400 by 399, we get 6 with a remainder of 6.
The next digit of our result is 6. 
Result so far: 220275.84962406
If we subtract 2394 from 2400, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

After the division, we end up with 220275.84962406 and a remainder of 6e-09.