815815828613 has 24 divisors (see below), whose sum is σ = 918797964552. Its totient is φ = 721312929792.

The previous prime is 815815828609. The next prime is 815815828657. The reversal of 815815828613 is 316828518518.

It can be written as a sum of positive squares in 12 ways, for example, as 5920225249 + 809895603364 = 76943^2 + 899942^2 .

It is not a de Polignac number, because 815815828613 - 2² = 815815828609 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815815428613) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 242120 + ... + 1300097.

It is an arithmetic number, because the mean of its divisors is an integer number (38283248523).

Almost surely, 2^815815828613 is an apocalyptic number.

It is an amenable number.

815815828613 is a deficient number, since it is larger than the sum of its proper divisors (102982135939).

815815828613 is a wasteful number, since it uses less digits than its factorization.

815815828613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1542329 (or 1542300 counting only the distinct ones).

The product of its digits is 3686400, while the sum is 56.

The spelling of 815815828613 in words is "eight hundred fifteen billion, eight hundred fifteen million, eight hundred twenty-eight thousand, six hundred thirteen".