18038865 has 16 divisors (see below), whose sum is σ = 31082688. Its totient is φ = 8880576.

The previous prime is 18038861. The next prime is 18038897. The reversal of 18038865 is 56883081.

It is a happy number.

It is not a de Polignac number, because 18038865 - 2² = 18038861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (18038861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46059 + ... + 46448.

It is an arithmetic number, because the mean of its divisors is an integer number (1942668).

Almost surely, 2^18038865 is an apocalyptic number.

18038865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18038865 is a deficient number, since it is larger than the sum of its proper divisors (13043823).

18038865 is a wasteful number, since it uses less digits than its factorization.

18038865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92528.

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 18038865 is about 4247.2185015608. The cubic root of 18038865 is about 262.2626244111.

The spelling of 18038865 in words is "eighteen million, thirty-eight thousand, eight hundred sixty-five".