For a three-digit number, the number in the hundreds place is 5 times the number in the ones place, and the number in the tens place is equal to the sum of the numbers in the hundreds place and the ones place. What is this number?
一个三位数，百位上的数字是个位上数字的5倍，十位上的数字等于百位上与个位上数字的和，这个数是多少．
<result>561</result>