why number 8549176320 is one of a kind?

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

What does an Island and the letter T have in common?

I am an eight letter word and I am a computer terminology.
The second, third and fourth letters make an animal.
The fourth, fifth, sixth, seventh and eighth letters make a weapon.
The first, second, third and fourth letters can be taken as an outcome of any exam.
The fifth, sixth, seventh and eighth letter combine to form a high end typing software.

Can you tell who am I ?

Find out the missing number in the picture attached:

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

How can you tell a raw egg from a hard-boiled egg?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?