18641618 has 18 divisors (see below), whose sum is σ = 29036727. Its totient is φ = 8975820.

The previous prime is 18641561. The next prime is 18641621. The reversal of 18641618 is 81614681.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 9320809 + 9320809 = 3053^2 + 3053^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3053.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 262523 + ... + 262593.

Almost surely, 2^18641618 is an apocalyptic number.

18641618 is a deficient number, since it is larger than the sum of its proper divisors (10395109).

18641618 is an frugal number, since it uses more digits than its factorization.

18641618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 116 counting only the distinct ones).

The product of its digits is 9216, while the sum is 35.

The square root of 18641618 is about 4317.5940059251. The cubic root of 18641618 is about 265.1517725584.

The spelling of 18641618 in words is "eighteen million, six hundred forty-one thousand, six hundred eighteen".