659946509 has 2 divisors, whose sum is σ = 659946510. Its totient is φ = 659946508.

The previous prime is 659946503. The next prime is 659946523. The reversal of 659946509 is 905649956.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 471845284 + 188101225 = 21722^2 + 13715^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-659946509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (659946503) 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, 329973254 + 329973255.

It is an arithmetic number, because the mean of its divisors is an integer number (329973255).

Almost surely, 2^659946509 is an apocalyptic number.

It is an amenable number.

659946509 is a deficient number, since it is larger than the sum of its proper divisors (1).

659946509 is an equidigital number, since it uses as much as digits as its factorization.

659946509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2624400, while the sum is 53.

The square root of 659946509 is about 25689.4240690600. The cubic root of 659946509 is about 870.6352470636.

The spelling of 659946509 in words is "six hundred fifty-nine million, nine hundred forty-six thousand, five hundred nine".