18397767911 has 4 divisors (see below), whose sum is σ = 18400879992. Its totient is φ = 18394655832.

The previous prime is 18397767847. The next prime is 18397767923. The reversal of 18397767911 is 11976779381.

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 18397767911 - 2⁶ = 18397767847 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 (18397767961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1547156 + ... + 1559001.

It is an arithmetic number, because the mean of its divisors is an integer number (4600219998).

Almost surely, 2^18397767911 is an apocalyptic number.

18397767911 is a deficient number, since it is larger than the sum of its proper divisors (3112081).

18397767911 is an equidigital number, since it uses as much as digits as its factorization.

18397767911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3112080.

The product of its digits is 4000752, while the sum is 59.

The spelling of 18397767911 in words is "eighteen billion, three hundred ninety-seven million, seven hundred sixty-seven thousand, nine hundred eleven".