18351668687 has 4 divisors (see below), whose sum is σ = 20020002216. Its totient is φ = 16683335160.

The previous prime is 18351668683. The next prime is 18351668689. The reversal of 18351668687 is 78686615381.

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 18351668687 - 2² = 18351668683 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 (18351668683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 834166748 + ... + 834166769.

It is an arithmetic number, because the mean of its divisors is an integer number (5005000554).

Almost surely, 2^18351668687 is an apocalyptic number.

18351668687 is a deficient number, since it is larger than the sum of its proper divisors (1668333529).

18351668687 is a wasteful number, since it uses less digits than its factorization.

18351668687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1668333528.

The product of its digits is 11612160, while the sum is 59.

The spelling of 18351668687 in words is "eighteen billion, three hundred fifty-one million, six hundred sixty-eight thousand, six hundred eighty-seven".