6402 ÷ 4 = 1600 R2
We're going to perform division on 6402 with 4 as the divisor.

Step 1:
4 goes into 6 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 4 from 6 to get 2.
Bring next digit (4) of the dividend behind the 2 and repeat the process: 24 / 4

Step 2:
4 goes into 24 6 times with a remainder of 0.
Write down 6 as next digit of of the result. 
Result so far: 16
Subtract 24 from 24 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 4

Step 3:
4 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 160
Subtract 0 from 0 to get 0.
Bring next digit (2) of the dividend behind the 0 and repeat the process: 2 / 4

Step 4:
4 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 1600
Subtract 0 from 2 to get 2.

The final result is 1600 with a remainder of 2.