18836850557 has 4 divisors (see below), whose sum is σ = 21527829216. Its totient is φ = 16145871900.

The previous prime is 18836850551. The next prime is 18836850677. The reversal of 18836850557 is 75505863881.

It is a happy number.

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 18836850557 - 2¹⁸ = 18836588413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18836850551) 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, 1345489319 + ... + 1345489332.

It is an arithmetic number, because the mean of its divisors is an integer number (5381957304).

Almost surely, 2^18836850557 is an apocalyptic number.

It is an amenable number.

18836850557 is a deficient number, since it is larger than the sum of its proper divisors (2690978659).

18836850557 is an equidigital number, since it uses as much as digits as its factorization.

18836850557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2690978658.

The product of its (nonzero) digits is 8064000, while the sum is 56.

The spelling of 18836850557 in words is "eighteen billion, eight hundred thirty-six million, eight hundred fifty thousand, five hundred fifty-seven".