18018655 has 4 divisors (see below), whose sum is σ = 21622392. Its totient is φ = 14414920.

The previous prime is 18018629. The next prime is 18018661. The reversal of 18018655 is 55681081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55681081 = 1237 ⋅45013.

It is a de Polignac number, because none of the positive numbers 2^k-18018655 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18018655.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1801861 + ... + 1801870.

It is an arithmetic number, because the mean of its divisors is an integer number (5405598).

Almost surely, 2^18018655 is an apocalyptic number.

18018655 is a deficient number, since it is larger than the sum of its proper divisors (3603737).

18018655 is an equidigital number, since it uses as much as digits as its factorization.

18018655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3603736.

The product of its (nonzero) digits is 9600, while the sum is 34.

The square root of 18018655 is about 4244.8386306195. The cubic root of 18018655 is about 262.1646450705.

The spelling of 18018655 in words is "eighteen million, eighteen thousand, six hundred fifty-five".