9

Nine is a composite number, its proper divisors being 1 and 3.  It is 3 times 3 and hence the third square number.  It is the first composite lucky number.  Nine is the highest single-digit number in the decimal system...

 

 What does 9 mean for this cute girl?

She's definitely lucky;

 3xs the excitement (thanks to 1 sister)

3 rows of 3 donuts;

1 girl surrounded by 3 lucky siblings.
We love her the highest amount possible!