729857 has 4 divisors (see below), whose sum is σ = 732720. Its totient is φ = 726996.

The previous prime is 729851. The next prime is 729871. The reversal of 729857 is 758927.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 758927 = 13 ⋅58379.

It is a cyclic number.

It is not a de Polignac number, because 729857 - 2⁸ = 729601 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 729857.

It is not an unprimeable number, because it can be changed into a prime (729851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1007 + ... + 1572.

It is an arithmetic number, because the mean of its divisors is an integer number (183180).

2⁷²⁹⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

729857 is a deficient number, since it is larger than the sum of its proper divisors (2863).

729857 is a wasteful number, since it uses less digits than its factorization.

729857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2862.

The product of its digits is 35280, while the sum is 38.

The square root of 729857 is about 854.3166860129. The cubic root of 729857 is about 90.0352536788.

The spelling of 729857 in words is "seven hundred twenty-nine thousand, eight hundred fifty-seven".