For a three-digit number, the number in the tens place is 4 greater than the number in the ones place, the number in the tens place is 1 less than the number in the hundreds place, and the sum of the numbers in the three places is less than 10. What is the number?
一个三位数，十位上的数比个位上的数大4，十位上的数比百位上的数小1，并且3个数位上的数字的和小于10，这个数是多少．
<result>540</result>