**`Integer constant`** in C is a data type that is represented by `const int`. **`const int`** is capable of storing an integer in decimal, octal, and hexadecimal bases. The value to `const int` is assigned only when it is declared and cannot be changed afterward.

# Declaration
The declaration of `const int` is shown below:


# Examples
Consider the table below, which shows examples of the declaration of `const int` in decimal, hexadecimal, and octal bases.

What is integer constant in C?

Integer constant in C is a `const int` that stores unchangeable integers in decimal, octal, or hexadecimal.

Data type	Value range (in decimal)	Decimal	Hexadecimal	Octal
int	-2147483648 to 2147483647	`const int num = -5;`	`const int num = 0x12345678;`	`const int num = 023;`
unsigned	0 to 4294967295	`const unsigned int num = 5;`	`const unsigned int num = 0x1AB5;`	`const unsigned int num = 023146;`
long	-9223372036854775807 to 9223372036854775807	`const long int num = 700000000;`	`const long int num = 0x1AB5114455667788;`	`const long int num = 012345671234567;`
unsigned long	0 to 1844674407370955169	`const unsigned long int num = 500000000;`	`const unsigned long int num = 0x1AB51144D56E7F8;`	`const unsigned long int num = 012345671234567;`