Find the next number in the series below

21 32 54 87 131 ?

There are three Athletes (John, Tarun and Harish) and their individual Coaches (Jacob, Meenaxi and Priyanka) standing on the shore.
No Coach trusts their Athlete to be near any other Coach unless they are also with them.
There is a boat that can hold a maximum of two persons.
How can the six people get across the river?

It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?

Can you name three consecutive days without using the words Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, or Sunday?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

Two friends were betting. One said to the other, "The coin will be flipped twenty times and each time the coin lands on the head, I will give you $2 and each time it lands on the tale, you will give me $3." After flipping the coin twenty times not a single penny was exchanged among them.

How many times did the coin land on heads?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

Can you find a five letter word that is left with only two letters if one is removed?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

Forwards I am heavy, backward I am not. What am I?