18706865 has 8 divisors (see below), whose sum is σ = 22996008. Its totient is φ = 14600320.

The previous prime is 18706861. The next prime is 18706873. The reversal of 18706865 is 56860781.

It can be written as a sum of positive squares in 4 ways, for example, as 2961841 + 15745024 = 1721^2 + 3968^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18706865 - 2² = 18706861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18706861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45422 + ... + 45831.

It is an arithmetic number, because the mean of its divisors is an integer number (2874501).

Almost surely, 2^18706865 is an apocalyptic number.

It is an amenable number.

18706865 is a deficient number, since it is larger than the sum of its proper divisors (4289143).

18706865 is an equidigital number, since it uses as much as digits as its factorization.

18706865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91299.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 18706865 is about 4325.1433502255. The cubic root of 18706865 is about 265.4607624165.

The spelling of 18706865 in words is "eighteen million, seven hundred six thousand, eight hundred sixty-five".