18115956 has 36 divisors (see below), whose sum is σ = 46230912. Its totient is φ = 5980944.

The previous prime is 18115939. The next prime is 18115967. The reversal of 18115956 is 65951181.

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a self number, because there is not a number n which added to its sum of digits gives 18115956.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1501 + ... + 6203.

It is an arithmetic number, because the mean of its divisors is an integer number (1284192).

Almost surely, 2^18115956 is an apocalyptic number.

It is an amenable number.

18115956 is an abundant number, since it is smaller than the sum of its proper divisors (28114956).

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

18115956 is a wasteful number, since it uses less digits than its factorization.

18115956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4820 (or 4815 counting only the distinct ones).

The product of its digits is 10800, while the sum is 36.

The square root of 18115956 is about 4256.2842950160. The cubic root of 18115956 is about 262.6356958282.

The spelling of 18115956 in words is "eighteen million, one hundred fifteen thousand, nine hundred fifty-six".