18388343869 has 4 divisors (see below), whose sum is σ = 21015250144. Its totient is φ = 15761437596.

The previous prime is 18388343863. The next prime is 18388343881. The reversal of 18388343869 is 96834388381.

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 18388343869 - 2³ = 18388343861 is a prime.

It is a super-2 number, since 2×18388343869² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18388343861) 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, 1313453127 + ... + 1313453140.

It is an arithmetic number, because the mean of its divisors is an integer number (5253812536).

Almost surely, 2^18388343869 is an apocalyptic number.

It is an amenable number.

18388343869 is a deficient number, since it is larger than the sum of its proper divisors (2626906275).

18388343869 is an equidigital number, since it uses as much as digits as its factorization.

18388343869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2626906274.

The product of its digits is 23887872, while the sum is 61.

The spelling of 18388343869 in words is "eighteen billion, three hundred eighty-eight million, three hundred forty-three thousand, eight hundred sixty-nine".