Is 42 a prime number?

Prime Number Checker
Number

Is 42 a prime or composite number?

Answer

Number 42 is not a Prime

42 = 2 × 3 × 7

42 has 8 divisors — 1, 2, 3, 6, 7, 14, 21 and 42; a prime has exactly two: 1 and itself.

Primes up to √42

6² = 36 ≤ 42 < 49 = 7², so it is enough to try primes up to 6

  • ÷2 divides

42 ÷ 2 = 21 — 2 divides 42, so 42 is composite

Nearest primes: 41 and 43

Related Calculations

See Also

Prime numbers list

NumberIs Prime
27No: 3³
28No: 2² × 7
29Yes
30No: 2 × 3 × 5
31Yes
32No: 2⁵
33No: 3 × 11
34No: 2 × 17
35No: 5 × 7
36No: 2² × 3²
37Yes
38No: 2 × 19
39No: 3 × 13
40No: 2³ × 5
41Yes
42No: 2 × 3 × 7
43Yes
44No: 2² × 11
45No: 3² × 5
46No: 2 × 23
47Yes
48No: 2⁴ × 3
49No: 7²
50No: 2 × 5²
51No: 3 × 17
52No: 2² × 13
53Yes
54No: 2 × 3³
55No: 5 × 11
56No: 2³ × 7

FAQ

Is 42 a prime or composite number?

Number 42 is not a Prime

How many factors are in a number 42?

8

How to check if 42 is prime?

Divide 42 by the primes in order: 6² = 36 ≤ 42 < 49 = 7², so it is enough to try primes up to 6. The first one that divides it is 2: 42 ÷ 2 = 21, so 42 is composite.

See Also