When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

How many letters are in the alphabet?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

What has to be broken before you can use it?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

What is the riddle which can be asked all day with a different correct answer each time.

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?