Can you find out which number multiplied by itself will give the output as 12345678987654321?

I have Rs.50 and I spend it in the way as below.

There are three houses in a straight row. One is red, one is blue, and one is white. The red house is left of the middle. The blue house is right of the middle. Where's the white house?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?

Move three sticks of the spiral below to form a square.

In a rainy season, one day 3 huge ladies walked under a normal-sized umbrella.
The umbrella is not huge enough to accommodate all 3 ladies yet not a single lady got wet. Why?

I’m tall when I’m young, and I’m short when I’m old. What am I?