18685351868537 has 8 divisors (see below), whose sum is σ = 18852644784456. Its totient is φ = 18518740390912.

The previous prime is 18685351868531. The next prime is 18685351868539. The reversal of 18685351868537 is 73586815358681.

It can be written as a sum of positive squares in 4 ways, for example, as 2598041080336 + 16087310788201 = 1611844^2 + 4010899^2 .

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

It is not a de Polignac number, because 18685351868537 - 2⁶ = 18685351868473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18685351868531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170304488 + ... + 170414169.

It is an arithmetic number, because the mean of its divisors is an integer number (2356580598057).

Almost surely, 2^{18685351868537} is an apocalyptic number.

It is an amenable number.

18685351868537 is a deficient number, since it is larger than the sum of its proper divisors (167292915919).

18685351868537 is a wasteful number, since it uses less digits than its factorization.

18685351868537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340719147.

The product of its digits is 1161216000, while the sum is 74.

The spelling of 18685351868537 in words is "eighteen trillion, six hundred eighty-five billion, three hundred fifty-one million, eight hundred sixty-eight thousand, five hundred thirty-seven".