## Strong Numbers

What are Strong Numbers?   Strong number is a special number such that sum of the factorial of its digits is equal to the original number.   Strong Numbers are also known as Peterson Numbers.   Examples of Strong Number     Let us understand Strong Number with an example.   145 is a … Read more

## What is an Abundant Number?

What is an Abundant Number? An Abundant Number is a positive integer for which the sum of all its Proper divisors (factors) is more than the original number.   Abundant number is  also called Excessive Numbers.     Examples of Abundant Numbers Let us understand Abundant Number with a few examples.     Example 1.  … Read more

## What is a Duck Number?

What is a Duck Number? Duck Number is a positive non-zero number which contains zero in it. It is to be noted that a number with leading zero, i.e. if a number begins with a zero, cannot be called a Duck Number. Zero must be present at any position other than the beginning. There could … Read more

## What is Armstrong Number?

What is Armstrong Number? An Armstrong Number is an integer such that the sum of its own digits each raised to the power of the number of the digits is equal to the number itself. Armstrong number is named after Michael F. Armstrong. It is also called a Narcissistic number.   Examples of Armstrong Number Let … Read more

## Handsome Number

What is a Handsome Number?   In Mathematics, Handsome number is a natural number in which the sum of all the left side digits is equal to the last digit.     Example of Handsome Numbers Let us understand Handsome numbers with few examples.    Example 1: 123   123 is a Handsome Number because … Read more

What is an Adam Number?   A number is called an Adam number, if the square of a number and the square of its reverse are reverse to each other. Let us understand it through an example.     Example of Adam Number Let us take a number (N) = 13   The reverse of … Read more

## What are Dudeney Numbers?

Dudeney number is named after an English mathematician, Henry Dudeney, who used them in puzzles he created.    What is a Dudeney Number?   Dudeney number is a positive integer that is a perfect cube such that sum of its digits is equal to its own cube root.   For example, 512 is a Dudeney … Read more

## What is a Spy Number?

Do you know What is a Spy Number? If you are in an opinion that it must be a number which secretly conveys information about other numbers like a spy, then you are absolutely wrong. What is a Spy Number?   Definition of a Spy number: A spy number is that positive integer, whose sum … Read more

## What are Emirp Numbers?

Do you know what is an Emirp Number? If you look at the word Emirp carefully, you will observe that it is the word “Prime” spelled in reverse order. Hence, it is quite evident that an Emirp number is related to a Prime number.    What are Emirp Numbers?   Definition: We can define … Read more