18668685017 has 4 divisors (see below), whose sum is σ = 18671373876. Its totient is φ = 18665996160.

The previous prime is 18668685001. The next prime is 18668685019. The reversal of 18668685017 is 71058686681.

It is a happy number.

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 16211400976 + 2457284041 = 127324^2 + 49571^2 .

It is a cyclic number.

It is not a de Polignac number, because 18668685017 - 2⁴ = 18668685001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18668685019) 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, 1333988 + ... + 1347909.

It is an arithmetic number, because the mean of its divisors is an integer number (4667843469).

Almost surely, 2^18668685017 is an apocalyptic number.

It is an amenable number.

18668685017 is a deficient number, since it is larger than the sum of its proper divisors (2688859).

18668685017 is an equidigital number, since it uses as much as digits as its factorization.

18668685017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2688858.

The product of its (nonzero) digits is 3870720, while the sum is 56.

The spelling of 18668685017 in words is "eighteen billion, six hundred sixty-eight million, six hundred eighty-five thousand, seventeen".