664786589 has 2 divisors, whose sum is σ = 664786590. Its totient is φ = 664786588.

The previous prime is 664786567. The next prime is 664786597. The reversal of 664786589 is 985687466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 661364089 + 3422500 = 25717^2 + 1850^2 .

It is a cyclic number.

It is not a de Polignac number, because 664786589 - 2¹² = 664782493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664786559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332393294 + 332393295.

It is an arithmetic number, because the mean of its divisors is an integer number (332393295).

Almost surely, 2^664786589 is an apocalyptic number.

It is an amenable number.

664786589 is a deficient number, since it is larger than the sum of its proper divisors (1).

664786589 is an equidigital number, since it uses as much as digits as its factorization.

664786589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17418240, while the sum is 59.

The square root of 664786589 is about 25783.4557226141. The cubic root of 664786589 is about 872.7584920042.

The spelling of 664786589 in words is "six hundred sixty-four million, seven hundred eighty-six thousand, five hundred eighty-nine".