669239 has 4 divisors (see below), whose sum is σ = 708624. Its totient is φ = 629856.

The previous prime is 669181. The next prime is 669241. The reversal of 669239 is 932966.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 932966 = 2 ⋅466483.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669239 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 669199 and 669208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669289) 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 3 ways as a sum of consecutive naturals, for example, 19667 + ... + 19700.

It is an arithmetic number, because the mean of its divisors is an integer number (177156).

2⁶⁶⁹²³⁹ is an apocalyptic number.

669239 is a deficient number, since it is larger than the sum of its proper divisors (39385).

669239 is a wasteful number, since it uses less digits than its factorization.

669239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39384.

The product of its digits is 17496, while the sum is 35.

The square root of 669239 is about 818.0702903785. The cubic root of 669239 is about 87.4702592802.

The spelling of 669239 in words is "six hundred sixty-nine thousand, two hundred thirty-nine".