813811860 has 84 divisors (see below), whose sum is σ = 2562381108. Its totient is φ = 217012608.

The previous prime is 813811849. The next prime is 813811877. The reversal of 813811860 is 68118318.

It can be written as a sum of positive squares in 2 ways, for example, as 619711236 + 194100624 = 24894^2 + 13932^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 13329 + ... + 42488.

It is an arithmetic number, because the mean of its divisors is an integer number (30504537).

Almost surely, 2^813811860 is an apocalyptic number.

It is an amenable number.

813811860 is an abundant number, since it is smaller than the sum of its proper divisors (1748569248).

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

813811860 is a wasteful number, since it uses less digits than its factorization.

813811860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55844 (or 55827 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 813811860 is about 28527.3878930406. The cubic root of 813811860 is about 933.6297275775.

The spelling of 813811860 in words is "eight hundred thirteen million, eight hundred eleven thousand, eight hundred sixty".