The no. of four digit even numbers that can be formed with 0,1,2,3,7,8?

That depends on what you mean by "four digits". Is 0000 a four digit number? Assuming the answer is no, you have five choices for the first digit, six for the second digit, six for the third digit, and three for the fourth digit. 5 x 6 x 6 x 3 = 540