18349172069 has 4 divisors (see below), whose sum is σ = 18395392044. Its totient is φ = 18302952096.

The previous prime is 18349172041. The next prime is 18349172077. The reversal of 18349172069 is 96027194381.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13083928225 + 5265243844 = 114385^2 + 72562^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18349172069 is a prime.

It is a super-2 number, since 2×18349172069² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18349172669) 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, 23109392 + ... + 23110185.

It is an arithmetic number, because the mean of its divisors is an integer number (4598848011).

Almost surely, 2^18349172069 is an apocalyptic number.

It is an amenable number.

18349172069 is a deficient number, since it is larger than the sum of its proper divisors (46219975).

18349172069 is an equidigital number, since it uses as much as digits as its factorization.

18349172069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46219974.

The product of its (nonzero) digits is 653184, while the sum is 50.

The spelling of 18349172069 in words is "eighteen billion, three hundred forty-nine million, one hundred seventy-two thousand, sixty-nine".