819681688 has 32 divisors (see below), whose sum is σ = 1759737600. Its totient is φ = 350636832.

The previous prime is 819681677. The next prime is 819681697. The reversal of 819681688 is 886186918.

819681688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17253 + ... + 44011.

It is an arithmetic number, because the mean of its divisors is an integer number (54991800).

Almost surely, 2^819681688 is an apocalyptic number.

It is an amenable number.

819681688 is an abundant number, since it is smaller than the sum of its proper divisors (940055912).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

819681688 is a wasteful number, since it uses less digits than its factorization.

819681688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27319 (or 27315 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 55.

The square root of 819681688 is about 28630.0836184598. The cubic root of 819681688 is about 935.8690340782.

The spelling of 819681688 in words is "eight hundred nineteen million, six hundred eighty-one thousand, six hundred eighty-eight".