# What is a happy number?

**Happy number**. A

**happy number**is defined by the following process: Starting with any positive integer, replace the

**number**by the sum of the squares of its digits in base-ten, and repeat the process until the

**number**either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1.

A.

### What is the perfect number?

In

**number**theory, a**perfect number**is a positive integer that is equal to the sum of its proper positive divisors, that is, the sum of its positive divisors excluding the**number**itself (also known as its aliquot sum).#### WHY IS 496 a perfect number?

Also related to its being a**perfect number**,**496**is a harmonic divisor**number**, since the**number**of proper divisors of**496**divided by the sum of the reciprocals of its divisors, 1, 2, 4, 8, 16, 31, 62, 124, 248 and**496**, (the harmonic mean), yields an integer, 5 in this case. It is the largest happy**number**less than 500.#### What is meant by narcissistic number?

In recreational**number**theory, a**narcissistic number**(also known as a pluperfect digital invariant (PPDI), an Armstrong**number**(after Michael F. Armstrong) or a plus perfect**number**) is a**number**that is the sum of its own digits each raised to the power of the**number**of digits.#### What is a group of twelve called?

The usual ordinal form is "twelfth" but "dozenth" or "duodecimal" (from the Latin word) is also used in some contexts, particularly base-12 numeration. Similarly, a**group of twelve**things is usually a "dozen" but may also be referred to as a "duodecad".

B.

### What is meant by Adam Number?

**Adam Number**.

**Adam number**is a

**number**when reversed, the square of the

**number**and the square of the reversed

**number**should be

**numbers**which are reverse of each other.

**Adam numbers**upto 1000 are: 0, 1, 2, 3, 11, 12, 13, 21, 22, 31, 101, 102, 103, 111, 112 , 113, 121, 122, 201, 202, 211, 212, 221, 301, 311.

#### What is meant by Adam Number?

**Adam number**is a**number**when reversed, the square of the**number**and the square of the reversed**number**should be**numbers**which are reverse of each other.**Adam numbers**upto 1000 are: 0, 1, 2, 3, 11, 12, 13, 21, 22, 31, 101, 102, 103, 111, 112 , 113, 121, 122, 201, 202, 211, 212, 221, 301, 311.#### What is the 888 area code?

The area codes or prefixes**800**, 833,**844**,**855**,**866**,**877**and 888 are used by toll free numbers in the United States, Canada and all the countries covered by the North American Numbering Plan.#### What does it mean when you see 222?

**2:22**: Seek balance. Two is the number of partnership and relationships. When you see**2:22**, pay attention to the people who are showing up in your world. You might be bumping into a soulmate, or a soul friend, someone who will play a significant role in your world.

C.

### What are the Armstrong numbers?

An

**Armstrong number**of three digits is an integer such that the sum of the cubes of its digits is equal to the**number**itself. For example, 371 is an**Armstrong number**since 3**3 + 7**3 + 1**3 = 371. Write a program to find all**Armstrong number**in the range of 0 and 999.#### What is a perfect no?

**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.#### What is a palindrome number?

A**palindromic number**or numeral**palindrome**is a**number**that remains the same when its digits are reversed. Like 16461, for example, it is "symmetrical". The term**palindromic**is derived from**palindrome**, which refers to a word (such as rotor or racecar) whose spelling is unchanged when its letters are reversed.#### What is prime number in C?

**Prime number**program in**C**.**Prime number**program in**C**:**C**program for**prime number**, this code prints**prime numbers**using**C**programming language.**C**program to check whether a**number**is**prime**or not.**Prime number**logic: a**number**is**prime**if it is divisible only by one and itself.

Updated: 3rd October 2019