2, 3, 5, 9, 17, _ What is the next number in the sequence?

Suppose we lay down two cups in front of you. One of the cups is filled with tea and the other one with coffee. Now we ask you to take a spoonful of tea and mix it with the coffee. At this moment, the coffee cup has a mixture of tea and coffee. You have to take that mixture (spoonful) and add it back to the tea.

Can you now tell if the cup of coffee has more tea or the cup of tea has more coffee?

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

With the help clues provided in the image, can you find the 5 digit key?

Pronounced as 1 letter, And written with 3, 2 letters there are, and 2 only in me. I’m double, I’m single, I’m black blue and grey, I’m read from both ends, and the same either way. What am I?

He runs but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

In a rainy season, one day 3 huge ladies walked under a normal-sized umbrella.
The umbrella is not huge enough to accommodate all 3 ladies yet not a single lady got wet. Why?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?