Can you fill the blank with the correct number?

6 30 870 756030 _____

John went to a parrot shop in Mexico, and the parrot owner told him that his parrot is so unique that he repeats everything he hears. John got excited and immediately bought the parrot. John went home and spoke many words, but the parrot does not repeat anything.
He went again to the parrot shop and complaint to the shopkeeper, but the shopkeeper never lied. Explain?

I travel all around the world but always stay in the corner. What am I?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

When is the top of a mountain similar to a savings account?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

What have one eye but still cannot see?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Three friends named Mr. Black, Mr. Yellow and Mr. Green enter a pub on a weekend night. They are wearing either a Black, Yellow or Green shirt.

Mr. Yellow says to them, 'Did you notice that we all are wearing different color shirts than our names?'

To this, the man who was wearing the Green shirt said. 'Wow, thats right.'

Can you identify who is wearing which colour shirt ?

I was born in a small house and I live in it all alone. No windows and no doors have been assigned to my house. The only way I can go out is by breaking through the walls of my house.

Who am I?