655390909 has 2 divisors, whose sum is σ = 655390910. Its totient is φ = 655390908.

The previous prime is 655390891. The next prime is 655390937. The reversal of 655390909 is 909093556.

It is a happy number.

655390909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 334085284 + 321305625 = 18278^2 + 17925^2 .

It is a cyclic number.

It is not a de Polignac number, because 655390909 - 2¹⁹ = 654866621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (655390969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327695454 + 327695455.

It is an arithmetic number, because the mean of its divisors is an integer number (327695455).

Almost surely, 2^655390909 is an apocalyptic number.

It is an amenable number.

655390909 is a deficient number, since it is larger than the sum of its proper divisors (1).

655390909 is an equidigital number, since it uses as much as digits as its factorization.

655390909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 328050, while the sum is 46.

The square root of 655390909 is about 25600.6036842884. The cubic root of 655390909 is about 868.6272926839.

The spelling of 655390909 in words is "six hundred fifty-five million, three hundred ninety thousand, nine hundred nine".