18381591307 has 4 divisors (see below), whose sum is σ = 18382070016. Its totient is φ = 18381112600.

The previous prime is 18381591299. The next prime is 18381591317. The reversal of 18381591307 is 70319518381.

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 18381591307 - 2³ = 18381591299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18381591317) 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, 176203 + ... + 260404.

It is an arithmetic number, because the mean of its divisors is an integer number (4595517504).

Almost surely, 2^18381591307 is an apocalyptic number.

18381591307 is a deficient number, since it is larger than the sum of its proper divisors (478709).

18381591307 is an equidigital number, since it uses as much as digits as its factorization.

18381591307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 478708.

The product of its (nonzero) digits is 181440, while the sum is 46.

The spelling of 18381591307 in words is "eighteen billion, three hundred eighty-one million, five hundred ninety-one thousand, three hundred seven".