why number 8549176320 is one of a kind?

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognises the three as friends and asks the waiter to return $5 to the men.

The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.

Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14. Where has the other $1 gone from the original $15?

Find the Odd One Out?
84129
32418
47632
36119
67626
72927

What makes this number unique: 8,549,176,320?

A convention is held where all the big logicians are summoned. The master places a band on everyone's forehead. Now all of them can see others bands but can't see his own. Then they are told that there are different colours of bands. All the logicians sit in circle and they are further explained that a bell will ring at regular intervals. The moment when a logician knew the colour of band on his forehead, he will leave at the next bell. If anyone leaves at the wrong bell, he will be disqualified.

The master assures the logicians that the puzzle will not be impossible for anyone of them. How will the logicians manage ?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

Which is heavier: a ton of bricks or a ton of feathers?

Okay before we begin with the puzzle, do keep in mind that you have to answer it quickly.

You are participating in a car race. Seeking the perfect moment, you overtake the second person in the race. What positions are you in now?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?