815815812 has 48 divisors (see below), whose sum is σ = 2234314880. Its totient is φ = 226789632.

The previous prime is 815815789. The next prime is 815815831. The reversal of 815815812 is 218518518.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128137 + ... + 134352.

Almost surely, 2^815815812 is an apocalyptic number.

It is an amenable number.

815815812 is an abundant number, since it is smaller than the sum of its proper divisors (1418499068).

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

815815812 is a wasteful number, since it uses less digits than its factorization.

815815812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262540 (or 262538 counting only the distinct ones).

The product of its digits is 25600, while the sum is 39.

The square root of 815815812 is about 28562.4895973723. The cubic root of 815815812 is about 934.3954309944.

The spelling of 815815812 in words is "eight hundred fifteen million, eight hundred fifteen thousand, eight hundred twelve".