669209 has 8 divisors (see below), whose sum is σ = 696960. Its totient is φ = 642096.

The previous prime is 669181. The next prime is 669241. The reversal of 669209 is 902966.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 669209 - 2¹² = 665113 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669209.

It is not an unprimeable number, because it can be changed into a prime (669289) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3299 + ... + 3495.

It is an arithmetic number, because the mean of its divisors is an integer number (87120).

2⁶⁶⁹²⁰⁹ is an apocalyptic number.

It is an amenable number.

669209 is a deficient number, since it is larger than the sum of its proper divisors (27751).

669209 is a wasteful number, since it uses less digits than its factorization.

669209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 669209 is about 818.0519543403. The cubic root of 669209 is about 87.4689522499.

It can be divided in two parts, 669 and 209, that added together give a palindrome (878).

The spelling of 669209 in words is "six hundred sixty-nine thousand, two hundred nine".