18381591361 has 8 divisors (see below), whose sum is σ = 21008678400. Its totient is φ = 15754790688.

The previous prime is 18381591353. The next prime is 18381591373. The reversal of 18381591361 is 16319518381.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18381591361 - 2³ = 18381591353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18381591341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90405 + ... + 211981.

It is an arithmetic number, because the mean of its divisors is an integer number (2626084800).

Almost surely, 2^18381591361 is an apocalyptic number.

It is an amenable number.

18381591361 is a deficient number, since it is larger than the sum of its proper divisors (2627087039).

18381591361 is a wasteful number, since it uses less digits than its factorization.

18381591361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143183.

The product of its digits is 155520, while the sum is 46.

The spelling of 18381591361 in words is "eighteen billion, three hundred eighty-one million, five hundred ninety-one thousand, three hundred sixty-one".