18520368667 has 4 divisors (see below), whose sum is σ = 19609802136. Its totient is φ = 17430935200.

The previous prime is 18520368631. The next prime is 18520368677. The reversal of 18520368667 is 76686302581.

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 18520368667 - 2¹⁹ = 18519844379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18520368677) 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, 544716709 + ... + 544716742.

It is an arithmetic number, because the mean of its divisors is an integer number (4902450534).

Almost surely, 2^18520368667 is an apocalyptic number.

18520368667 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

18520368667 is a deficient number, since it is larger than the sum of its proper divisors (1089433469).

18520368667 is a wasteful number, since it uses less digits than its factorization.

18520368667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1089433468.

The product of its (nonzero) digits is 2903040, while the sum is 52.

The spelling of 18520368667 in words is "eighteen billion, five hundred twenty million, three hundred sixty-eight thousand, six hundred sixty-seven".