18945231289 has 2 divisors, whose sum is σ = 18945231290. Its totient is φ = 18945231288.

The previous prime is 18945231241. The next prime is 18945231313. The reversal of 18945231289 is 98213254981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18849093264 + 96138025 = 137292^2 + 9805^2 .

It is a cyclic number.

It is not a de Polignac number, because 18945231289 - 2⁷ = 18945231161 is a prime.

It is not a weakly prime, because it can be changed into another prime (18945231589) 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, 9472615644 + 9472615645.

It is an arithmetic number, because the mean of its divisors is an integer number (9472615645).

Almost surely, 2^18945231289 is an apocalyptic number.

It is an amenable number.

18945231289 is a deficient number, since it is larger than the sum of its proper divisors (1).

18945231289 is an equidigital number, since it uses as much as digits as its factorization.

18945231289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1244160, while the sum is 52.

The spelling of 18945231289 in words is "eighteen billion, nine hundred forty-five million, two hundred thirty-one thousand, two hundred eighty-nine".