18645057909 has 12 divisors (see below), whose sum is σ = 26934200800. Its totient is φ = 12428907624.

The previous prime is 18645057901. The next prime is 18645057947. The reversal of 18645057909 is 90975054681.

18645057909 is a `hidden beast` number, since 1 + 8 + 64 + 5 + 0 + 579 + 0 + 9 = 666.

It is not a de Polignac number, because 18645057909 - 2³ = 18645057901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18645057901) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17082 + ... + 193860.

Almost surely, 2^18645057909 is an apocalyptic number.

It is an amenable number.

18645057909 is a deficient number, since it is larger than the sum of its proper divisors (8289142891).

18645057909 is a wasteful number, since it uses less digits than its factorization.

18645057909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188504 (or 188501 counting only the distinct ones).

The product of its (nonzero) digits is 2721600, while the sum is 54.

The spelling of 18645057909 in words is "eighteen billion, six hundred forty-five million, fifty-seven thousand, nine hundred nine".