18500001685 has 8 divisors (see below), whose sum is σ = 24218184096. Its totient is φ = 13454546640.

The previous prime is 18500001661. The next prime is 18500001787. The reversal of 18500001685 is 58610000581.

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

It is a de Polignac number, because none of the positive numbers 2^k-18500001685 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18500001685.

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, 168181779 + ... + 168181888.

It is an arithmetic number, because the mean of its divisors is an integer number (3027273012).

Almost surely, 2^18500001685 is an apocalyptic number.

It is an amenable number.

18500001685 is a deficient number, since it is larger than the sum of its proper divisors (5718182411).

18500001685 is a wasteful number, since it uses less digits than its factorization.

18500001685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336363683.

The product of its (nonzero) digits is 9600, while the sum is 34.

The spelling of 18500001685 in words is "eighteen billion, five hundred million, one thousand, six hundred eighty-five".