18393913691 has 16 divisors (see below), whose sum is σ = 19817239680. Its totient is φ = 17008848000.

The previous prime is 18393913679. The next prime is 18393913771. The reversal of 18393913691 is 19631939381.

It is a cyclic number.

It is not a de Polignac number, because 18393913691 - 2¹⁸ = 18393651547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18393913631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2253680 + ... + 2261826.

It is an arithmetic number, because the mean of its divisors is an integer number (1238577480).

Almost surely, 2^18393913691 is an apocalyptic number.

18393913691 is a deficient number, since it is larger than the sum of its proper divisors (1423325989).

18393913691 is a wasteful number, since it uses less digits than its factorization.

18393913691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10474.

The product of its digits is 944784, while the sum is 53.

The spelling of 18393913691 in words is "eighteen billion, three hundred ninety-three million, nine hundred thirteen thousand, six hundred ninety-one".