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

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?

What is harder to catch the faster you run?

Things are just as they seem, right? Well, check again.
Can you count the number of tigers in this picture ?

Spot what is wrong here in below Picture?

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?