Definition of strong number:
A
number is called strong number if sum of the factorial of its digit is equal to
number itself. For example: 145 since
1! + 4! + 5! = 1 + 24 +
120 = 145
Showing posts with label C Programs. Show all posts
Showing posts with label C Programs. Show all posts
To Check Prime Number
A
natural number greater than one has not any other divisors except 1 and itself.
In other word we can say which has only two divisors 1 and number itself. For
example: 5
Their
divisors are 1 and 5.
Note: 2
is only even prime number.
Logic for
prime number in c
We will
take a loop and divide number from 2 to number/2. If the number is not divisible
by any of the numbers then we will print it as prime number.
Example of 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, 101, 103, 107, 109,
113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197,
199 etc.
To Check Armstrong Number
Definition of Armstrong number or what is an
Armstrong number:
Definition according to c programming point of view:
Those numbers which sum of the cube of its digits is equal to that number are known as Armstrong numbers. For example 153 since 1^3 + 5^3 + 3^3 = 1+ 125 + 9 =153
Other Armstrong numbers: 370,371,407 etc.
To Check Perfect Number
Definition
of perfect number or What is perfect number?
Perfect
number is a positive number which sum of all positive divisors excluding that
number is equal to that number. For example 6 is perfect number since divisor
of 6 are 1, 2 and 3. Sum of its divisor
is
1 + 2+ 3 =6
Note: 6 is the smallest perfect
number.
Next perfect number is 28 since 1+
2 + 4 + 7 + 14 = 28
Some more perfect numbers: 496,
8128
