Is 171 a prime number?

Prime Number Checker
Number

Is 171 a prime or composite number?

Answer

Number 171 is not a Prime

171 = 3² × 19

171 has 6 divisors — 1, 3, 9, 19, 57 and 171; a prime has exactly two: 1 and itself.

Primes up to √171

13² = 169 ≤ 171 < 196 = 14², so it is enough to try primes up to 13

  • ÷2 does not divide
  • ÷3 divides

171 ÷ 3 = 57 — 3 divides 171, so 171 is composite

Nearest primes: 167 and 173

Related Calculations

See Also

Prime numbers list

NumberIs Prime
150No: 2 × 3 × 5²
151Yes
152No: 2³ × 19
153No: 3² × 17
154No: 2 × 7 × 11
156No: 2² × 3 × 13
157Yes
158No: 2 × 79
159No: 3 × 53
161No: 7 × 23
162No: 2 × 3⁴
163Yes
167Yes
169No: 13²
170No: 2 × 5 × 17
171No: 3² × 19
173Yes
174No: 2 × 3 × 29
175No: 5² × 7
177No: 3 × 59
179Yes
180No: 2² × 3² × 5
181Yes
182No: 2 × 7 × 13
183No: 3 × 61
184No: 2³ × 23
186No: 2 × 3 × 31
187No: 11 × 17
189No: 3³ × 7
191Yes

FAQ

Is 171 a prime or composite number?

Number 171 is not a Prime

How many factors are in a number 171?

6

How to check if 171 is prime?

Divide 171 by the primes in order: 13² = 169 ≤ 171 < 196 = 14², so it is enough to try primes up to 13. The first one that divides it is 3: 171 ÷ 3 = 57, so 171 is composite.

See Also