728223891 has 8 divisors (see below), whose sum is σ = 978377664. Its totient is φ = 481776360.

The previous prime is 728223841. The next prime is 728223913. The reversal of 728223891 is 198322827.

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 728223891 - 2²⁹ = 191352979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (728223841) 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, 926101 + ... + 926886.

It is an arithmetic number, because the mean of its divisors is an integer number (122297208).

Almost surely, 2^728223891 is an apocalyptic number.

728223891 is a deficient number, since it is larger than the sum of its proper divisors (250153773).

728223891 is a wasteful number, since it uses less digits than its factorization.

728223891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1853121.

The product of its digits is 96768, while the sum is 42.

The square root of 728223891 is about 26985.6237837853. The cubic root of 728223891 is about 899.6805001713.

The spelling of 728223891 in words is "seven hundred twenty-eight million, two hundred twenty-three thousand, eight hundred ninety-one".