For a seven-digit number, the highest digit is 9, which is three times the number in the adjacent digit; the sum of the numbers in the thousands and hundreds digits is 8, and the difference is 4, and the numbers in the other digits are all 0, what is this number.
一个七位数，最高位上的数字是9，是与它相邻数位上的数字的3倍；千位和百位上的数字之和是8，差是4，其它各位上的数字都是0，这个数是多少．
<result>9_306_200</result>