18668536685 has 8 divisors (see below), whose sum is σ = 22769494296. Its totient is φ = 14689995840.

The previous prime is 18668536633. The next prime is 18668536693. The reversal of 18668536685 is 58663586681.

It can be written as a sum of positive squares in 4 ways, for example, as 1342343044 + 17326193641 = 36638^2 + 131629^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18668536685 - 2³² = 14373569389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30603854 + ... + 30604463.

It is an arithmetic number, because the mean of its divisors is an integer number (2846186787).

Almost surely, 2^18668536685 is an apocalyptic number.

It is an amenable number.

18668536685 is a deficient number, since it is larger than the sum of its proper divisors (4100957611).

18668536685 is an equidigital number, since it uses as much as digits as its factorization.

18668536685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61208383.

The product of its digits is 49766400, while the sum is 62.

The spelling of 18668536685 in words is "eighteen billion, six hundred sixty-eight million, five hundred thirty-six thousand, six hundred eighty-five".