18009655 has 4 divisors (see below), whose sum is σ = 21611592. Its totient is φ = 14407720.

The previous prime is 18009637. The next prime is 18009659. The reversal of 18009655 is 55690081.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 18009655 - 2⁷ = 18009527 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 18009655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18009659) 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 3 ways as a sum of consecutive naturals, for example, 1800961 + ... + 1800970.

It is an arithmetic number, because the mean of its divisors is an integer number (5402898).

Almost surely, 2^18009655 is an apocalyptic number.

18009655 is a deficient number, since it is larger than the sum of its proper divisors (3601937).

18009655 is an equidigital number, since it uses as much as digits as its factorization.

18009655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3601936.

The product of its (nonzero) digits is 10800, while the sum is 34.

The square root of 18009655 is about 4243.7783872394. The cubic root of 18009655 is about 262.1209889309.

The spelling of 18009655 in words is "eighteen million, nine thousand, six hundred fifty-five".