 # How Many Different Phone Numbers Are Possible?

## Will we ever run out of phone numbers?

According to forecasts by the North American Numbering Plan Administrator — that’s the official clearinghouse for area codes in the U.S., Canada and some Caribbean countries — D.C.’s (202) phone numbers could run out as early as the second quarter of 2023..

## How do you calculate the number of possible combinations?

Combinations Formula. Looking at the equation to calculate combinations, you can see that factorials are used throughout the formula. Remember, the formula to calculate combinations is nCr = n! / r! * (n – r)!, where n represents the number of items, and r represents the number of items being chosen at a time.

## How many combinations of 5 numbers are there?

Assuming no five-digit number can begin with zero, there are 9 possible choices for the first digit. Then there are 10 possible choices for each of the remaining four digits. Therefore, you have 9 x 10 x 10 x 10 x 10 combinations, or 9 x 10^4, which is 90,000 different combinations.

## How many combinations of 6 numbers are there in 59?

45,057,474The number of combinations possible with 6 numbers between 1 and 59 is 45,057,474.

## How many combinations of 12 numbers are there?

Combinations. So 479001600 combinations are possible if repetition is not allowed. If repetition of digits is allowed then, 12^12 combinations are possible. So 8916100400000 combinations are possible if repetition is allowed.

## What is the oldest phone number?

In the early 1930’s, it was given the phone number “PE6-5000”— in today’s phone parlance the letters P and E become 7 and 3 respectively, giving it the number 212-736-5000. Still in use today, it’s the longest continually operating phone number.

## What area code is 666?

Toward the end of 2007, the small town of Reeves, Louisiana, finally rid itself of a telephone area code that had been bedeviling its citizens since the 1960s — 666. Christians in Reeves were unhappy having the “number of the beast” for their prefix since being assigned it.

## What is nPr formula?

Definition: nPr(n,r) = n! / (n-r)! nCr(n, r) The number of different, unordered combinations of r objects from a set of n objects. Definition: nCr(n,r) = nPr(n,r) / r!

## Why is 555 a fake number?

Narrator: The short answer is that most 555 numbers are not working numbers, so real people won’t be harassed if diehard fans try to call them. 555 was an exchange combination that was not used very often in the American telephone system. You may get a wrong number, or no number at all.

## How many combinations are there in a 10 digit number?

9,999,999,999If you have 10 digits then the maximum number possible is: 9,999,999,999. Since the sequence starts at 0 we need to add 1. So 10,000,000,000 (10 billion).

## How do we not run out of phone numbers?

With ten digits, assuming a non-zero first digit, you can have 9,000,000,000 phone numbers. The population of the US (2012) is 313.9 million, or 313,900,000. This means, given the current population, you have to give out about 29 numbers to each person to run out.

## How many combinations of 7 numbers are there?

127The number of combinations that are possible with 7 numbers is 127.

## What are the possible combinations of 6 numbers?

Answer and Explanation: For any group of 6 numbers and letters, there are a possible 720 different permutations or combinations that can be made.

## How many ways can you make the number 25?

13Note: There are 13 different ways to make 25 cents with quarters, dimes, nickels, and pennies.

## How many combinations of 50 numbers are there?

All Possible Number Combinations For 5/1-50 Lottery Games Included with Your Order: All Possible 5/50 Number Combinations. Total Combinations – 2,118,760.