18887681232017 has 4 divisors (see below), whose sum is σ = 20340579788340. Its totient is φ = 17434782675696.

The previous prime is 18887681231999. The next prime is 18887681232029. The reversal of 18887681232017 is 71023218678881.

It is a Cunningham number, because it is equal to 4345996²+1.

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 2794032599296 + 16093648632721 = 1671536^2 + 4011689^2 .

It is a cyclic number.

It is not a de Polignac number, because 18887681232017 - 2²⁶ = 18887614123153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18887681232047) 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, 726449278142 + ... + 726449278167.

It is an arithmetic number, because the mean of its divisors is an integer number (5085144947085).

Almost surely, 2^{18887681232017} is an apocalyptic number.

It is an amenable number.

18887681232017 is a deficient number, since it is larger than the sum of its proper divisors (1452898556323).

18887681232017 is a wasteful number, since it uses less digits than its factorization.

18887681232017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1452898556322.

The product of its (nonzero) digits is 14450688, while the sum is 62.

The spelling of 18887681232017 in words is "eighteen trillion, eight hundred eighty-seven billion, six hundred eighty-one million, two hundred thirty-two thousand, seventeen".