What is the next number in this matchsticks series riddle?

Find out the missing number in the picture attached:

What has one letter and starts with an E?

What has 13 hearts but no other organs?

John is 45 years older than his son Jacob. If you find similarities between their ages, both of their ages contain prime numbers as the digits. Also, John's age is the reverse of Jacob's age.

Can you find their ages?

Take one out and scratch my head, I am now black but once was red. What am I?

It is always ahead of me yet I can never see it. What is it?

"That Restaurant always remains crowded. This is the reason why nobody goes there".

Can you find a flaw in this statement?

Who can jump higher than a Mountain?

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?