729909 has 6 divisors (see below), whose sum is σ = 1054326. Its totient is φ = 486600.

The previous prime is 729907. The next prime is 729913. The reversal of 729909 is 909927.

729909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 680625 + 49284 = 825^2 + 222^2 .

It is not a de Polignac number, because 729909 - 2¹ = 729907 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729907) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40542 + ... + 40559.

It is an arithmetic number, because the mean of its divisors is an integer number (175721).

2⁷²⁹⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

729909 is a deficient number, since it is larger than the sum of its proper divisors (324417).

729909 is a wasteful number, since it uses less digits than its factorization.

729909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81107 (or 81104 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 729909 is about 854.3471191501. The cubic root of 729909 is about 90.0373918702.

The spelling of 729909 in words is "seven hundred twenty-nine thousand, nine hundred nine".