Starting from right for the number 85642,

Place value of 2 is ones

Place value of 4 is tens

Place value of 6 is hundred

Place value of 5 is thousand

Place value of 8 is ten thousand

Since, we need to round off to nearest thousands, all digits following 5 should be replaced by 0 and as the digit succeeding 5 is 6(greater than 5), therefore digit at ten thousand's place should be increment by 1,

∴ Answer = 86000