289684561 has 2 divisors, whose sum is σ = 289684562. Its totient is φ = 289684560.

The previous prime is 289684541. The next prime is 289684579. The reversal of 289684561 is 165486982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 169650625 + 120033936 = 13025^2 + 10956^2 .

It is a cyclic number.

It is not a de Polignac number, because 289684561 - 2⁵ = 289684529 is a prime.

It is not a weakly prime, because it can be changed into another prime (289684511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 144842280 + 144842281.

It is an arithmetic number, because the mean of its divisors is an integer number (144842281).

Almost surely, 2^289684561 is an apocalyptic number.

It is an amenable number.

289684561 is a deficient number, since it is larger than the sum of its proper divisors (1).

289684561 is an equidigital number, since it uses as much as digits as its factorization.

289684561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 829440, while the sum is 49.

The square root of 289684561 is about 17020.1222381039. The cubic root of 289684561 is about 661.6705164526.

The spelling of 289684561 in words is "two hundred eighty-nine million, six hundred eighty-four thousand, five hundred sixty-one".