Factors of 4
There are 3 factors of 4 — the full list is below, with factor pairs, prime factorization, and divisibility notes.
Factors of 4
1, 2, 4
Factor pairs of 4
- 1 × 4
- 2 × 2
Prime factorization of 4
4 = 2²
Number facts
- 4 is a composite number.
- 4 has 3 factors.
- 4 is a perfect square.
- The sum of all factors of 4 is 7.
Divisibility rules that apply to 4
- 4 is divisible by 2 because it ends in an even digit (0, 2, 4, 6, or 8).
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How the factors of 4 are calculated
To find the factors of 4, every whole number from 1 up to the square root of 4(about 2.00) is tested for even division. 4 is even, and it divides evenly by 2. Written as a product of primes, 4 = 2². 4 is also a perfect square, which is why one of its factor pairs is a number multiplied by itself.
Frequently asked questions about 4
How many factors does 4 have?
4 has 3 factors: 1, 2, 4.
Is 4 a prime number?
No. 4 is composite because it has factors other than 1 and itself.
What are the factor pairs of 4?
The factor pairs of 4 are 1 × 4, 2 × 2.
What is the prime factorization of 4?
The prime factorization of 4 is 2².