18353668687 has 4 divisors (see below), whose sum is σ = 18605088880. Its totient is φ = 18102248496.

The previous prime is 18353668679. The next prime is 18353668769. The reversal of 18353668687 is 78686635381.

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

It is a cyclic number.

It is not a de Polignac number, because 18353668687 - 2³ = 18353668679 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 (18353668387) 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, 125709987 + ... + 125710132.

It is an arithmetic number, because the mean of its divisors is an integer number (4651272220).

Almost surely, 2^18353668687 is an apocalyptic number.

18353668687 is a deficient number, since it is larger than the sum of its proper divisors (251420193).

18353668687 is an equidigital number, since it uses as much as digits as its factorization.

18353668687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251420192.

The product of its digits is 34836480, while the sum is 61.

The spelling of 18353668687 in words is "eighteen billion, three hundred fifty-three million, six hundred sixty-eight thousand, six hundred eighty-seven".