18240655 has 4 divisors (see below), whose sum is σ = 21888792. Its totient is φ = 14592520.

The previous prime is 18240641. The next prime is 18240659. The reversal of 18240655 is 55604281.

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

It is not a de Polignac number, because 18240655 - 2⁷ = 18240527 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18240659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1824061 + ... + 1824070.

It is an arithmetic number, because the mean of its divisors is an integer number (5472198).

Almost surely, 2^18240655 is an apocalyptic number.

18240655 is a deficient number, since it is larger than the sum of its proper divisors (3648137).

18240655 is an equidigital number, since it uses as much as digits as its factorization.

18240655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3648136.

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 18240655 is about 4270.9079830874. The cubic root of 18240655 is about 263.2369254879.

The spelling of 18240655 in words is "eighteen million, two hundred forty thousand, six hundred fifty-five".