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

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

I am a mother. However, I never give birth.

I am a father. However, I never nurse my children.

Wandering is not possible for me, but standing still happens occurs rarely.

Who am I?

Three people are in a room. Ronni looks at the Nile. The Nile looks at Senthil. Ronni is married but Senthil is not married. At any point, is a married person looking at an unmarried person? Yes, No or Cannot be determined.

What makes this number unique: 8,549,176,320?

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

What country can make you shiver?

They are three errirs in this question. Can you find them?

What can go through glass without breaking it?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.