729391 has 8 divisors (see below), whose sum is σ = 827120. Its totient is φ = 637632.

The previous prime is 729389. The next prime is 729403. The reversal of 729391 is 193927.

729391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 6-Lehmer number, since φ(729391) divides (729391-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 729391 - 2¹ = 729389 is a prime.

It is a super-2 number, since 2×729391² = 1064022461762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1230 + ... + 1723.

It is an arithmetic number, because the mean of its divisors is an integer number (103390).

2⁷²⁹³⁹¹ is an apocalyptic number.

729391 is a deficient number, since it is larger than the sum of its proper divisors (97729).

729391 is a wasteful number, since it uses less digits than its factorization.

729391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2985.

The product of its digits is 3402, while the sum is 31.

The square root of 729391 is about 854.0439098782. The cubic root of 729391 is about 90.0160876591.

The spelling of 729391 in words is "seven hundred twenty-nine thousand, three hundred ninety-one".