18046821589 has 2 divisors, whose sum is σ = 18046821590. Its totient is φ = 18046821588.

The previous prime is 18046821581. The next prime is 18046821643. The reversal of 18046821589 is 98512864081.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18027090225 + 19731364 = 134265^2 + 4442^2 .

It is a cyclic number.

It is not a de Polignac number, because 18046821589 - 2³ = 18046821581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18046821581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9023410794 + 9023410795.

It is an arithmetic number, because the mean of its divisors is an integer number (9023410795).

Almost surely, 2^18046821589 is an apocalyptic number.

It is an amenable number.

18046821589 is a deficient number, since it is larger than the sum of its proper divisors (1).

18046821589 is an equidigital number, since it uses as much as digits as its factorization.

18046821589 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1105920, while the sum is 52.

The spelling of 18046821589 in words is "eighteen billion, forty-six million, eight hundred twenty-one thousand, five hundred eighty-nine".