664890559 has 2 divisors, whose sum is σ = 664890560. Its totient is φ = 664890558.

The previous prime is 664890547. The next prime is 664890613. The reversal of 664890559 is 955098466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664890559 - 2¹⁹ = 664366271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664896559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332445279 + 332445280.

It is an arithmetic number, because the mean of its divisors is an integer number (332445280).

Almost surely, 2^664890559 is an apocalyptic number.

664890559 is a deficient number, since it is larger than the sum of its proper divisors (1).

664890559 is an equidigital number, since it uses as much as digits as its factorization.

664890559 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2332800, while the sum is 52.

The square root of 664890559 is about 25785.4718591691. The cubic root of 664890559 is about 872.8039882942.

The spelling of 664890559 in words is "six hundred sixty-four million, eight hundred ninety thousand, five hundred fifty-nine".