728851688 has 8 divisors (see below), whose sum is σ = 1366596930. Its totient is φ = 364425840.

The previous prime is 728851687. The next prime is 728851699. The reversal of 728851688 is 886158827.

728851688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 678185764 + 50665924 = 26042^2 + 7118^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (728851687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45553223 + ... + 45553238.

Almost surely, 2^728851688 is an apocalyptic number.

It is an amenable number.

728851688 is a deficient number, since it is larger than the sum of its proper divisors (637745242).

728851688 is a wasteful number, since it uses less digits than its factorization.

728851688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91106467 (or 91106463 counting only the distinct ones).

The product of its digits is 1720320, while the sum is 53.

The square root of 728851688 is about 26997.2533417753. The cubic root of 728851688 is about 899.9389621157.

The spelling of 728851688 in words is "seven hundred twenty-eight million, eight hundred fifty-one thousand, six hundred eighty-eight".