9-digit Number Puzzle

What 9-digit number has the following features:

It has all 9 digits from 1 to 9

It can be exactly divided by 6 and 7

Each time it is rounded (starting with units, then tens, hundreds, etc) it rounds in an alternate pattern (up, down, up, ...), until after rounding 8 times the final number is 500000000

After rounding four times the sum of the digits is 24

Bonus: what is the solution if the rounding goes down, up, down, ...