18608639861 has 4 divisors (see below), whose sum is σ = 21267016992. Its totient is φ = 15950262732.

The previous prime is 18608639789. The next prime is 18608639867. The reversal of 18608639861 is 16893680681.

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 18608639861 - 2¹⁴ = 18608623477 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18608639797 and 18608639806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18608639867) 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, 1329188555 + ... + 1329188568.

It is an arithmetic number, because the mean of its divisors is an integer number (5316754248).

Almost surely, 2^18608639861 is an apocalyptic number.

It is an amenable number.

18608639861 is a deficient number, since it is larger than the sum of its proper divisors (2658377131).

18608639861 is an equidigital number, since it uses as much as digits as its factorization.

18608639861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2658377130.

The product of its (nonzero) digits is 2985984, while the sum is 56.

The spelling of 18608639861 in words is "eighteen billion, six hundred eight million, six hundred thirty-nine thousand, eight hundred sixty-one".