18582809891 has 2 divisors, whose sum is σ = 18582809892. Its totient is φ = 18582809890.

The previous prime is 18582809881. The next prime is 18582810011. The reversal of 18582809891 is 19890828581.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18582809891 - 2⁶ = 18582809827 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18582809891.

It is not a weakly prime, because it can be changed into another prime (18582809801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9291404945 + 9291404946.

It is an arithmetic number, because the mean of its divisors is an integer number (9291404946).

Almost surely, 2^18582809891 is an apocalyptic number.

18582809891 is a deficient number, since it is larger than the sum of its proper divisors (1).

18582809891 is an equidigital number, since it uses as much as digits as its factorization.

18582809891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3317760, while the sum is 59.

The spelling of 18582809891 in words is "eighteen billion, five hundred eighty-two million, eight hundred nine thousand, eight hundred ninety-one".