The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

What is more useful when it is broken?

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

What does below chemistry rebus means?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

I know a country, If you remove the last alphabet of its name, it will become a part of your body. Do you name it?

What country can make you shiver?