18506500805 has 8 divisors (see below), whose sum is σ = 23916093432. Its totient is φ = 13666339008.

The previous prime is 18506500769. The next prime is 18506500813. The reversal of 18506500805 is 50800560581.

It can be written as a sum of positive squares in 4 ways, for example, as 2067844 + 18504432961 = 1438^2 + 136031^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 18506500805 - 2¹² = 18506496709 is a prime.

It is a Duffinian number.

It is a Curzon 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, 142357634 + ... + 142357763.

It is an arithmetic number, because the mean of its divisors is an integer number (2989511679).

Almost surely, 2^18506500805 is an apocalyptic number.

It is an amenable number.

18506500805 is a deficient number, since it is larger than the sum of its proper divisors (5409592627).

18506500805 is a wasteful number, since it uses less digits than its factorization.

18506500805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284715415.

The product of its (nonzero) digits is 48000, while the sum is 38.

The spelling of 18506500805 in words is "eighteen billion, five hundred six million, five hundred thousand, eight hundred five".