811865860 has 36 divisors (see below), whose sum is σ = 1846161828. Its totient is φ = 299764608.

The previous prime is 811865833. The next prime is 811865861. The reversal of 811865860 is 68568118.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 54405376 + 757460484 = 7376^2 + 27522^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (811865861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 116719 + ... + 123478.

It is an arithmetic number, because the mean of its divisors is an integer number (51282273).

Almost surely, 2^811865860 is an apocalyptic number.

It is an amenable number.

811865860 is an abundant number, since it is smaller than the sum of its proper divisors (1034295968).

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

811865860 is a wasteful number, since it uses less digits than its factorization.

811865860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240232 (or 240217 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 811865860 is about 28493.2599047564. The cubic root of 811865860 is about 932.8849634942.

The spelling of 811865860 in words is "eight hundred eleven million, eight hundred sixty-five thousand, eight hundred sixty".