18591340439 has 12 divisors (see below), whose sum is σ = 21628902168. Its totient is φ = 15933783600.

The previous prime is 18591340409. The next prime is 18591340447. The reversal of 18591340439 is 93404319581.

It is a de Polignac number, because none of the positive numbers 2^k-18591340439 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18591340393 and 18591340402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18591340409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 822884 + ... + 845174.

It is an arithmetic number, because the mean of its divisors is an integer number (1802408514).

Almost surely, 2^18591340439 is an apocalyptic number.

18591340439 is a deficient number, since it is larger than the sum of its proper divisors (3037561729).

18591340439 is a wasteful number, since it uses less digits than its factorization.

18591340439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39326 (or 39319 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 47.

The spelling of 18591340439 in words is "eighteen billion, five hundred ninety-one million, three hundred forty thousand, four hundred thirty-nine".