655944689 has 2 divisors, whose sum is σ = 655944690. Its totient is φ = 655944688.

The previous prime is 655944617. The next prime is 655944701. The reversal of 655944689 is 986449556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 574800625 + 81144064 = 23975^2 + 9008^2 .

It is a cyclic number.

It is not a de Polignac number, because 655944689 - 2²⁰ = 654896113 is a prime.

It is not a weakly prime, because it can be changed into another prime (655944089) 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, 327972344 + 327972345.

It is an arithmetic number, because the mean of its divisors is an integer number (327972345).

Almost surely, 2^655944689 is an apocalyptic number.

It is an amenable number.

655944689 is a deficient number, since it is larger than the sum of its proper divisors (1).

655944689 is an equidigital number, since it uses as much as digits as its factorization.

655944689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9331200, while the sum is 56.

The square root of 655944689 is about 25611.4171611022. The cubic root of 655944689 is about 868.8718759780.

The spelling of 655944689 in words is "six hundred fifty-five million, nine hundred forty-four thousand, six hundred eighty-nine".