18886813217 has 4 divisors (see below), whose sum is σ = 18992326320. Its totient is φ = 18781300116.

The previous prime is 18886813213. The next prime is 18886813241. The reversal of 18886813217 is 71231868881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18886813217 - 2² = 18886813213 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18886813213) 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, 52756283 + ... + 52756640.

It is an arithmetic number, because the mean of its divisors is an integer number (4748081580).

Almost surely, 2^18886813217 is an apocalyptic number.

It is an amenable number.

18886813217 is a deficient number, since it is larger than the sum of its proper divisors (105513103).

18886813217 is a wasteful number, since it uses less digits than its factorization.

18886813217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105513102.

The product of its digits is 1032192, while the sum is 53.

The spelling of 18886813217 in words is "eighteen billion, eight hundred eighty-six million, eight hundred thirteen thousand, two hundred seventeen".