Is 729 a prime number?

Prime Number Checker
Number

Is 729 a prime or composite number?

Answer

Number 729 is not a Prime

729 = 3⁶

729 has 7 divisors — 1, 3, 9, 27, 81, 243 and 729; a prime has exactly two: 1 and itself. It is a perfect square.

Primes up to √729

27² = 729 ≤ 729 < 784 = 28², so it is enough to try primes up to 27

  • ÷2 does not divide
  • ÷3 divides

729 ÷ 3 = 243 — 3 divides 729, so 729 is composite

Nearest primes: 727 and 733

Related Calculations

See Also

Prime numbers list

NumberIs Prime
699No: 3 × 233
701Yes
702No: 2 × 3³ × 13
703No: 19 × 37
705No: 3 × 5 × 47
707No: 7 × 101
709Yes
711No: 3² × 79
713No: 23 × 31
716No: 2² × 179
719Yes
721No: 7 × 103
723No: 3 × 241
724No: 2² × 181
727Yes
729No: 3⁶
731No: 17 × 43
732No: 2² × 3 × 61
733Yes
736No: 2⁵ × 23
737No: 11 × 67
738No: 2 × 3² × 41
739Yes
741No: 3 × 13 × 19
742No: 2 × 7 × 53
743Yes
748No: 2² × 11 × 17
750No: 2 × 3 × 5³
751Yes
753No: 3 × 251

FAQ

Is 729 a prime or composite number?

Number 729 is not a Prime

How many factors are in a number 729?

7

How to check if 729 is prime?

Divide 729 by the primes in order: 27² = 729 ≤ 729 < 784 = 28², so it is enough to try primes up to 27. The first one that divides it is 3: 729 ÷ 3 = 243, so 729 is composite.

See Also