728989 has 4 divisors (see below), whose sum is σ = 737856. Its totient is φ = 720124.

The previous prime is 728971. The next prime is 728993. The reversal of 728989 is 989827.

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.

It is a cyclic number.

It is not a de Polignac number, because 728989 - 2⁹ = 728477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4309 + ... + 4474.

It is an arithmetic number, because the mean of its divisors is an integer number (184464).

2⁷²⁸⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

728989 is a deficient number, since it is larger than the sum of its proper divisors (8867).

728989 is an equidigital number, since it uses as much as digits as its factorization.

728989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8866.

The product of its digits is 72576, while the sum is 43.

The square root of 728989 is about 853.8085265444. The cubic root of 728989 is about 89.9995473228. Note that the first 3 decimals are identical.

The spelling of 728989 in words is "seven hundred twenty-eight thousand, nine hundred eighty-nine".