# What Are Happy And Sad Numbers?

## Is 5555 a happy number?

Also you get numbers that add up to other happy numbers e.g.

5555 – four fives squared = 100.

These are fixed points so they are happy numbers and any numbers which start sequences ending like this are happy numbers..

## What is the weirdest number?

Examples. The smallest weird number is 70. Its proper divisors are 1, 2, 5, 7, 10, 14, and 35; these sum to 74, but no subset of these sums to 70. The number 12, for example, is abundant but not weird, because the proper divisors of 12 are 1, 2, 3, 4, and 6, which sum to 16; but 2 + 4 + 6 = 12.

## Is 888 a happy number?

The distinct combinations of digits that form 10-happy numbers below 1000 are (the rest are just rearrangements and/or insertions of zero digits): 1, 7, 13, 19, 23, 28, 44, 49, 68, 79, 129, 133, 139, 167, 188, 226, 236, 239, 338, 356, 367, 368, 379, 446, 469, 478, 556, 566, 888, 899. (sequence A124095 in the OEIS).

## What are neon numbers?

A neon number is a number where the sum of digits of square of the number is equal to the number. The task is to check and print neon numbers in a range. … Input : 9 Output : Neon Number Explanation: square is 9*9 = 81 and sum of the digits of the square is 9.

## What is the most perfect number?

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. The discovery of such numbers is lost in prehistory.

## What number is the most powerful?

9Which is the strongest number? Number 9 is the strongest number among all numbers. Number 9 stands for initiation, wisdom, and spiritual enlightenment. When number 9 is multiplied with other numbers, the result will always reduce to 9.

## What numbers are happy numbers?

is said to be happy. For example, starting with 7 gives the sequence 7, 49, 97, 130, 10, 1, so 7 is a happy number. The first few happy numbers are 1, 7, 10, 13, 19, 23, 28, 31, 32, 44, 49, 68, 70, 79, 82, 86, 91, 94, 97, 100, … (OEIS A007770).

## How do I know my happy number?

To find out if a number is happy, replace the number by the sum of the squares of its digits. Repeat the process until either the number equals 1 or loops endlessly in a cycle that does not include 1. When the process ends with 1 then the number is described as a happy number, otherwise, it is an unhappy number.

## Is 12 a triangular number?

For example, the digital root of 12, which is not a triangular number, is 3 and divisible by three.

## What is happy number in Java?

Introduction to Happy Numbers in Java. Happy Number are positive non-zero integer numbers. If we find the sum of the squares of its every digit and repeat that process until the number will be equals to 1(one). Otherwise, it is called Unhappy Number or Sad Number.

## Why is 70 a weird number?

Weird numbers are natural numbers that are abundant but not semiperfect. For example, 70 is the lowest weird number, because its set of proper divisors {1,2,5,7,10,14,35} sum to 74, but no subset of its set of proper divisors sum to the number 70, and 70 is the smallest number to meet such conditions.

## What is a sad number?

An unhappy number is a number that is not happy, i.e., a number such that iterating this sum-of-squared-digits map starting with. never reaches the number 1. The first few unhappy numbers are 2, 3, 4, 5, 6, 8, 9, 11, 12, 14, 15, 16, 17, 18, 20, …

## Is Python a happy number?

A number is said to be happy if it yields 1 when replaced by the sum of squares of its digits repeatedly. If this process results in an endless cycle of numbers containing 4, then the number will be an unhappy number.

## What is the definition of prime number?

a positive integer that is not divisible without remainder by any integer except itself and 1, with 1 often excluded: The integers 2, 3, 5, and 7 are prime numbers.

## Is 13 a Fibonacci number?

The Fibonacci Sequence is the series of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, …