669609 has 12 divisors (see below), whose sum is σ = 988416. Its totient is φ = 436632.

The previous prime is 669607. The next prime is 669611. The reversal of 669609 is 906966.

It is an interprime number because it is at equal distance from previous prime (669607) and next prime (669611).

It is not a de Polignac number, because 669609 - 2¹ = 669607 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669609.

It is not an unprimeable number, because it can be changed into a prime (669607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 369 + ... + 1214.

It is an arithmetic number, because the mean of its divisors is an integer number (82368).

2⁶⁶⁹⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

669609 is a deficient number, since it is larger than the sum of its proper divisors (318807).

669609 is a wasteful number, since it uses less digits than its factorization.

669609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1636 (or 1633 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 669609 is about 818.2964010675. The cubic root of 669609 is about 87.4863761101.

The spelling of 669609 in words is "six hundred sixty-nine thousand, six hundred nine".