• My age
• My house number
• The sum of those first two numbers
• The difference between those first two numbers
• Half of one of those first four numbers

I chose to write down the names of the numbers in letters rather than use digits (e.g. "thirty six").
Surprisingly, I noticed that each of the five numbers had the same number of letters in its name.

What were the last three numbers I wrote?

I think I have the solution.  The first two numbers are 32 and 49.  Their Sum is 81.  The difference between them is 17.  And 98 is 2 x 49.

All five numbers have nine letters.