18857666423 has 4 divisors (see below), whose sum is σ = 18858372768. Its totient is φ = 18856960080.

The previous prime is 18857666419. The next prime is 18857666447. The reversal of 18857666423 is 32466675881.

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 18857666423 - 2² = 18857666419 is a prime.

It is a super-2 number, since 2×18857666423² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18857666473) 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, 311486 + ... + 367067.

It is an arithmetic number, because the mean of its divisors is an integer number (4714593192).

Almost surely, 2^18857666423 is an apocalyptic number.

18857666423 is a deficient number, since it is larger than the sum of its proper divisors (706345).

18857666423 is an equidigital number, since it uses as much as digits as its factorization.

18857666423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 706344.

The product of its digits is 11612160, while the sum is 56.

The spelling of 18857666423 in words is "eighteen billion, eight hundred fifty-seven million, six hundred sixty-six thousand, four hundred twenty-three".