813729 has 8 divisors (see below), whose sum is σ = 1240000. Its totient is φ = 464976.

The previous prime is 813721. The next prime is 813749. The reversal of 813729 is 927318.

It is a happy number.

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

It is not a de Polignac number, because 813729 - 2³ = 813721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 813696 and 813705.

It is not an unprimeable number, because it can be changed into a prime (813721) 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, 19354 + ... + 19395.

It is an arithmetic number, because the mean of its divisors is an integer number (155000).

2⁸¹³⁷²⁹ is an apocalyptic number.

It is an amenable number.

813729 is a deficient number, since it is larger than the sum of its proper divisors (426271).

813729 is a wasteful number, since it uses less digits than its factorization.

813729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38759.

The product of its digits is 3024, while the sum is 30.

The square root of 813729 is about 902.0692878044. The cubic root of 813729 is about 93.3598039998.

The spelling of 813729 in words is "eight hundred thirteen thousand, seven hundred twenty-nine".