Number Choosing Contest.

I have never regretted a single word so much in my life.

W: the number must be a positive integer
X: the number itself must be represented in base 10 Arabic numerals
Y: the number must have at least two formatting tags applied to it
Z: number must be presented with or by a TRUE fact about said number expressed in words

1: must have a Collatz Conjecture stopping time of at most 20
2: must be a happy number
3: must have a base-36 representation consisting only of letters
4: must have a composite number of prime factors
5: the decimal representation of its reciprocal must be periodic, with said period being at least 10

(there are precisely two numbers that pass all of the above rules, 736 & 40960, hence why "the answer is 736" was giving me kittens)

(posts akin to "the answer is ௭௩௬" passed Z technically because it is a fact that 736 is represented by those characters in that system)