18582809897 has 4 divisors (see below), whose sum is σ = 18583199316. Its totient is φ = 18582420480.

The previous prime is 18582809891. The next prime is 18582810011. The reversal of 18582809897 is 79890828581.

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 3383865241 + 15198944656 = 58171^2 + 123284^2 .

It is a cyclic number.

It is not a de Polignac number, because 18582809897 - 2⁴ = 18582809881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18582809891) 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, 111188 + ... + 222549.

It is an arithmetic number, because the mean of its divisors is an integer number (4645799829).

Almost surely, 2^18582809897 is an apocalyptic number.

It is an amenable number.

18582809897 is a deficient number, since it is larger than the sum of its proper divisors (389419).

18582809897 is an equidigital number, since it uses as much as digits as its factorization.

18582809897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389418.

The product of its (nonzero) digits is 23224320, while the sum is 65.

The spelling of 18582809897 in words is "eighteen billion, five hundred eighty-two million, eight hundred nine thousand, eight hundred ninety-seven".