Since the aliquot sums of prime numbers equal 1, **all prime numbers are deficient**. More generally, all odd numbers with one or two distinct prime factors are deficient. It follows that there are infinitely many odd deficient numbers.

## How do you tell if a number is abundant or deficient?

Every number can be classified as abundant, deficient, or perfect, according to the following definitions: Abundant: **The sum of the proper factors is greater than the number itself**. Deficient: The sum of the proper factors is less than the number itself.

No, 12 is not a prime number. The number 12 is divisible by 1, 2, 3, 4, 6, 12. For a number to be classified as a prime number, it should have exactly two factors. Since **12 has more than two factors**, i.e. 1, 2, 3, 4, 6, 12, it is not a prime number.

## Are there more deficient numbers than abundant numbers?

**Deficient numbers occur more frequently than abundant numbers**. In other words, the sum of the proper divisors of most numbers is less than the numbers themselves.

Examples. The first 28 **abundant** numbers are: 12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 102, 104, 108, 112, 114, 120, … (sequence A005101 in the OEIS).

## What is not a prime number?

Definition: A prime number is a whole number with exactly two integral divisors, 1 and itself. **The number 1 is not a prime, since it has only one divisor**. The number 4 is not prime, since it has three divisors ( 1 , 2 , and 4 ), and 6 is not prime, since it has four divisors ( 1 , 2 , 3 , and 6 ).

## Is 21 abundant or deficient?

## Why 1 is not a prime number?

**1 can only be divided by one number, 1 itself**, so with this definition 1 is not a prime number. It is important to remember that mathematical definitions develop and evolve. Throughout history, many mathematicians considered 1 to be a prime number although that is not now a commonly held view.

## How many prime numbers have been discovered?

In the 18th century Leonhard Euler proved that every even perfect number arises from a Mersenne prime in this way. and has over 49 million digits. We now know of **51 perfect numbers and 51 Mersenne primes**.

## What is the largest prime number up to 100?

So, there are total 25 prime numbers up to 100. Therefore, the prime numbers 1 to 100 can be listed as, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97.

## Are all abundant numbers even?

Examples of Abundant Numbers 12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100. In fact, **the first 60 abundant numbers are all even numbers!**

## Is 30 abundant deficient or perfect?

**30 is an abundant number**. The next possible sum is 12 + 20 = 32. 32 is not an abundant number. Its proper divisors are 1, 2, 4, 8 and 16 and their sum is 31, which is less than 32.

## Is 34 a deficient number?

Divisors of the Positive Integer 34 The integer 34 is an even number. The integer 34 is a Composite number. 20 is less than 34, so **34 is a deficient number**.

## Is 48 abundant deficient or perfect?

48 is called an **abundant number** because it is less than the sum of its factors (without itself).

## Is 64 an abundant number?

**Yes, 64 is a deficient number**, that is to say 64 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 64 without 64 itself (that is 1 + 2 + 4 + 8 + 16 + 32 = 63).

## Is 16 an abundant number?

The number 16 is greater than the number 12, so **12 is an abundant number**. The difference between the sum of the factors and the original number is known as the abundance. The abundance of 12 is 4, because 16 ” 12 = 4.

## Are all prime numbers odd?

First, **except for the number 2, all prime numbers are odd**, since an even number is divisible by 2, which makes it composite. So, the distance between any two prime numbers in a row (called successive prime numbers) is at least 2.

## What are all the prime numbers?

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 (sequence A000040 in the OEIS).

## Can negative numbers be prime?

Answer One: No. By the usual definition of prime for integers, **negative integers can not be prime**. By this definition, primes are integers greater than one with no positive divisors besides one and itself. Negative numbers are excluded.

## Is 49 a deficient number?

Properties of the number 49 8 is less than 49, so **49 is a deficient number**.

## Is 25 a deficient number?

In order for a number to be a deficient number, the sum of the proper factors of the number must be smaller than the number, not greater, or equal to the number. The first 20 deficient numbers are 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, and 25.

## Is 64 deficient perfect or abundant?

Yes, 64 is a **deficient number**, that is to say 64 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 64 without 64 itself (that is 1 + 2 + 4 + 8 + 16 + 32 = 63).

## Is 0 A prime number Yes or no?

**Zero is neither prime nor composite**. Since any number times zero equals zero, there are an infinite number of factors for a product of zero.

## Is 0 an even number?

So, let’s tackle 0 the same way as any other integer. **When 0 is divided by 2, the resulting quotient turns out to also be 0″an integer, thereby classifying it as an even number**.

## Is 0 A whole number?

In mathematics, **whole numbers are the basic counting numbers 0, 1, 2, 3, 4, 5, 6, … and so on**. 17, 99, 267, 8107 and 999999999 are examples of whole numbers. Whole numbers include natural numbers that begin from 1 onwards. Whole numbers include positive integers along with 0.

## Why is 11 not a prime number?

**The number 11 is divisible only by 1 and the number itself**. For a number to be classified as a prime number, it should have exactly two factors. Since 11 has exactly two factors, i.e. 1 and 11, it is a prime number.

## Who is the father of prime number?

History of prime numbers In 200 B.C., **Eratosthenes** created an algorithm that calculated prime numbers, known as the Sieve of Eratosthenes. This algorithm is one of the earliest algorithms ever written.

## Who named prime numbers?

At the beginning of the 17th century, French monk **Marin Mersenne** defined the prime numbers that bear his name, obtained as Mp = 2p ” 1. If p is a prime number, it is possible, though not certain, that Mp is also a prime number.

## What is the only even prime number?

The unique even prime number **2**. All other primes are odd primes.

## Is 13 a prime number Yes or no?

**Yes, 13 is a prime number**. The number 13 is divisible only by 1 and the number itself. For a number to be classified as a prime number, it should have exactly two factors. Since 13 has exactly two factors, i.e. 1 and 13, it is a prime number.

## Which number has more than two factors?

(b) A number which has more than two factors is called a **composite number**.

## What makes a number abundant?

## Is 5 a deficient number?

The first few deficient numbers are 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, … (OEIS A005100).

## Are there any odd abundant numbers?

The first 10 abundant numbers are: 12, 18, 20, 24, 30, 36, 40, 42, 48, 54,… The first 10 odd abundant numbers are: **945, 1575, 2205, 2835, 3465, 4095, 4725, 5355, 5775, 5985**,…

## What number is Kaprekar?

**6174** is known as Kaprekar’s constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule: Take any four-digit number, using at least two different digits (leading zeros are allowed).

## Is 24 a deficient number?

A perfect number is an integer that equals the sum of its proper divisors. For example, **24 is abundant, its divisors giving a sum of 36**; 32 is deficient, giving a sum…

## Is 496 deficient perfect or abundant?

perfect number, a positive integer that is equal to the sum of its proper divisors. The smallest perfect number is 6, which is the sum of 1, 2, and 3. Other **perfect numbers** are 28, 496, and 8,128.

## Is 1000 an abundant number?

J. Broscius (around 1652) showed that there are only 21 abundant numbers between 10 and 100 and all of them are even; **the only odd abundant number less than 1000 is 945**.

## What numbers can divide 100?

In simple words, 100 is a dividend and the divisors which will exactly divide it will be factors of 100. The factors of 100 are **1, 2, 4, 5, 10, 20, 25, 50 and 100**.

## Why is 1000 called an abundant number?

A number n is said to be Abundant Number **if sum of all the proper divisors of the number denoted by sum(n) is greater than the value of the number n**. And the difference between these two values is called the abundance.

## What does deficient mean in math?

deficient number. • **a number that is larger than the sum of its proper divisors**.

## What is the largest abundant number?

**7200** is the largest powerful number that is also highly abundant: all larger highly abundant numbers have a prime factor that divides them only once. Therefore, 7200 is also the largest highly abundant number with an odd sum of divisors.

## Is 55 a deficient number?

The integer 55 is a Composite number. 17 is less than 55, so **55 is a deficient number**.

## Why are all prime numbers not odd?

Explanation: By definition a prime number has only 2 factors ” itself and 1. Hence the smallest natural prime number is 2, and the only on that is even. All other prime numbers are odd, and there are infinitely many prime numbers.

## Do all prime numbers have 2 factors?

**A prime number has exactly two factors, 1 and itself**. For example, 13 is a prime number because the only factors of 13 are 1 and 13. The number 8 is not prime because it has four factors: 1, 2, 4 and 8. The number 1 is not a prime number because it only has one factor (itself).

## Why are all prime numbers except 2 odd?

Yes all prime numbers are odd except “2” because, **the remaining even numbers are multiples of “2”**. Prime number are those number which have only 2 factors i.e. 1 and number itself. so if any prime number (excluding 2) is even then its one of factor is 2. it means it has more then 2 factors.