728135881 has 8 divisors (see below), whose sum is σ = 795212928. Its totient is φ = 661206000.

The previous prime is 728135861. The next prime is 728135887. The reversal of 728135881 is 188531827.

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

It is a cyclic number.

It is not a de Polignac number, because 728135881 - 2⁷ = 728135753 is a prime.

It is a super-3 number, since 3×728135881³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728135887) 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, 26310 + ... + 46351.

It is an arithmetic number, because the mean of its divisors is an integer number (99401616).

Almost surely, 2^728135881 is an apocalyptic number.

It is an amenable number.

728135881 is a deficient number, since it is larger than the sum of its proper divisors (67077047).

728135881 is a wasteful number, since it uses less digits than its factorization.

728135881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73583.

The product of its digits is 107520, while the sum is 43.

The square root of 728135881 is about 26983.9930514370. The cubic root of 728135881 is about 899.6442548756.

The spelling of 728135881 in words is "seven hundred twenty-eight million, one hundred thirty-five thousand, eight hundred eighty-one".