49839 ÷ 4 = 12459 R3
Alright, let's work through the division of 49839 by 4 step by step.

Step 1:
4 goes into 4 1 times with a remainder of 0.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 4 from 4 to get 0.
Bring next digit (9) of the dividend behind the 0 and repeat the process: 9 / 4

Step 2:
4 goes into 9 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 12
Subtract 8 from 9 to get 1.
Bring next digit (8) of the dividend behind the 1 and repeat the process: 18 / 4

Step 3:
4 goes into 18 4 times with a remainder of 2.
Write down 4 as next digit of of the result. 
Result so far: 124
Subtract 16 from 18 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 4

Step 4:
4 goes into 23 5 times with a remainder of 3.
Write down 5 as next digit of of the result. 
Result so far: 1245
Subtract 20 from 23 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 4

Step 5:
4 goes into 39 9 times with a remainder of 3.
Write down 9 as next digit of of the result. 
Result so far: 12459
Subtract 36 from 39 to get 3.

The final result is 12459 with a remainder of 3.