Properties of Integers
Integers is the set of negative, zero and positive numbers, with no decimal or fraction part.
Example:
..., −4, −3, −2, −1, 0, 1, 2, 3, 4, ...
The following groups of numbers are included in integers:
1. Whole number
Whole number is integers that are not negative.
Example: 0, 1, 2, 3, 4, ...
2. Natural number
Natural number is the positive numbers of integers.
Example: 1, 2, 3, 4, ...
3. Even number
Even number is integers that divisible by two.
Example: ..., −6, −4, −2, 0, 2, 4, 6, ...
4. Odd number
Odd number is integers that have a remainder when divided by two.
Example: ..., −5, −3, −1, 1, 3, 5, ...
5. Prime number
Prime number is natural number that has two factors, 1 and and the number itself.
Example: 2, 3, 5, 7, 11, 13, 17, 19, 23, ...
6. Composite number
Composite number is natural number that has more than two factors.
Example: 4, 6, 8, 9, 10, 12, 14, …
7. Quadratic number
Quadratic number is natural number resulting from the square of a number.
Example: 1, 4, 9, 16, 25, 36, 49, …
8. Cubic number
Cubic number is natural number resulting from the cube of a number.
Example: 1, 8, 27, 64, 125, 216, 343, …
Properties of integers
1. Closure property
The operation of addition, subtraction and multiplication on integers will resulting an integers as well.
If a, b and c are integers, so the result of a + b × c is integers as well.
a + b × c ∈ Z
2. Commutative property of addition and multiplication
a + b = b + a
a × b = b × a
3. Associative property of addition and multiplication
(a + b) + c = a + (b + c)
(a × b) × c = a × (b × c)
4. Distributive property
a × (b + c) = (a × b) + (a × c)
a × (b − c) = (a × b) − (a × c)
5. Identity property
a + 0 = a
a × 1 = a
Exercise