813508071688 has 32 divisors (see below), whose sum is σ = 1699304002200. Its totient is φ = 362518184448.

The previous prime is 813508071679. The next prime is 813508071709. The reversal of 813508071688 is 886170805318.

It can be written as a sum of positive squares in 4 ways, for example, as 630051762564 + 183456309124 = 793758^2 + 428318^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134862381 + ... + 134868412.

Almost surely, 2^813508071688 is an apocalyptic number.

It is an amenable number.

813508071688 is an abundant number, since it is smaller than the sum of its proper divisors (885795930512).

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

813508071688 is a wasteful number, since it uses less digits than its factorization.

813508071688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269730841 (or 269730837 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 55.

The spelling of 813508071688 in words is "eight hundred thirteen billion, five hundred eight million, seventy-one thousand, six hundred eighty-eight".