We look at the division of 21415839 by 148 
Let's see how many times 148 fits into 21415839.

On to step 1:
If we divide 2 by 148, we get 0 and a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 148

Advancing to step 2:
21 divided by 148 is 0 with a remainder of 21.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 21, we get 21.
Grab the next digit (4) from the dividend, add it to 21, then carry on: 214 / 148

Moving on to step 3:
If we divide 214 by 148, we get 1 and a remainder of 66.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 148 from 214 to get 66.
Grab the next digit (1) from the dividend, add it to 66, then carry on: 661 / 148

Let's proceed to step 4:
661 divided by 148 is 4 with a remainder of 69.
The next digit of our result is 4. 
Result so far: 14.0
Subtracting 592 from 661 leaves us with 69.
Append the next digit (5) from the dividend to 69 and continue with: 695 / 148

Step 5:
148 goes into 695 4 times with a remainder of 103.
Put 4 as the next digit of the answer. 
Result so far: 144.0
If we subtract 592 from 695, we get 103.
Take the next digit (8) from the dividend and append it to 103, then repeat: 1038 / 148

On to step 6:
When dividing 1038 by 148, we get 7 with a remainder of 2.
The number 7 becomes the next digit in our result. 
Result so far: 1447.0
If we subtract 1036 from 1038, we get 2.
Include the next digit (3) from the dividend after 2, then repeat: 23 / 148

Moving on to step 7:
23 divided by 148 is 0 with a remainder of 23.
Record the quotient 0 as the next digit in the result. 
Result so far: 14470.0
If we subtract 0 from 23, we get 23.
Include the next digit (9) from the dividend after 23, then repeat: 239 / 148

Advancing to step 8:
When dividing 239 by 148, we get 1 with a remainder of 91.
Use 1 as the next digit of our solution. 
Result so far: 144701.0
Deduct 148 from 239 and we're left with 91.
Since there are no more digits in the dividend, we add a zero to the remainder making it 910, and continue the process.

Step 9:
148 goes into 910 6 times with a remainder of 22.
The next digit of our result is 6. 
Result so far: 144701.6
Deduct 888 from 910 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Moving on to step 10:
The number 148 fits into 220 1 times, leaving a remainder of 72.
Record the quotient 1 as the next digit in the result. 
Result so far: 144701.61
Deduct 148 from 220 and we're left with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 11:
148 goes into 720 4 times with a remainder of 128.
Write down 4 as next digit of the result. 
Result so far: 144701.614
If we subtract 592 from 720, we get 128.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1280, and continue the process.

On to step 12:
The number 148 fits into 1280 8 times, leaving a remainder of 96.
The next digit of our result is 8. 
Result so far: 144701.6148
The remainder is 96 after subtracting 1184 from 1280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

Step 13:
148 can be fit into 960 6 times, resulting in a remainder of 72.
Record the quotient 6 as the next digit in the result. 
Result so far: 144701.61486
Subtracting 888 from 960 leaves us with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Advancing to step 14:
If we divide 720 by 148, we get 4 and a remainder of 128.
Record the quotient 4 as the next digit in the result. 
Result so far: 144701.614864
Deduct 592 from 720 and we're left with 128.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1280, and continue the process.

Step 15:
When dividing 1280 by 148, we get 8 with a remainder of 96.
Put 8 as the next digit of the answer. 
Result so far: 144701.6148648
If we subtract 1184 from 1280, 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.

On to step 16:
The number 148 fits into 960 6 times, leaving a remainder of 72.
Write down 6 as next digit of the result. 
Result so far: 144701.61486486
The remainder is 72 after subtracting 888 from 960.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

The final outcome is 144701.61486486, with a leftover of 7.2e-08.