18345636609 has 4 divisors (see below), whose sum is σ = 24460848816. Its totient is φ = 12230424404.

The previous prime is 18345636563. The next prime is 18345636613. The reversal of 18345636609 is 90663654381.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18345636609 - 2¹³ = 18345628417 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18345636209) 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, 3057606099 + ... + 3057606104.

It is an arithmetic number, because the mean of its divisors is an integer number (6115212204).

Almost surely, 2^18345636609 is an apocalyptic number.

It is an amenable number.

18345636609 is a deficient number, since it is larger than the sum of its proper divisors (6115212207).

18345636609 is an equidigital number, since it uses as much as digits as its factorization.

18345636609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6115212206.

The product of its (nonzero) digits is 2799360, while the sum is 51.

The spelling of 18345636609 in words is "eighteen billion, three hundred forty-five million, six hundred thirty-six thousand, six hundred nine".