669385 has 4 divisors (see below), whose sum is σ = 803268. Its totient is φ = 535504.

The previous prime is 669379. The next prime is 669391. The reversal of 669385 is 583966.

669385 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 583966 = 2 ⋅291983.

It is an interprime number because it is at equal distance from previous prime (669379) and next prime (669391).

It can be written as a sum of positive squares in 2 ways, for example, as 328329 + 341056 = 573^2 + 584^2 .

It is a cyclic number.

It is not a de Polignac number, because 669385 - 2³ = 669377 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66934 + ... + 66943.

It is an arithmetic number, because the mean of its divisors is an integer number (200817).

2⁶⁶⁹³⁸⁵ is an apocalyptic number.

It is an amenable number.

669385 is a deficient number, since it is larger than the sum of its proper divisors (133883).

669385 is a wasteful number, since it uses less digits than its factorization.

669385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133882.

The product of its digits is 38880, while the sum is 37.

The square root of 669385 is about 818.1595198982. The cubic root of 669385 is about 87.4766196035.

The spelling of 669385 in words is "six hundred sixty-nine thousand, three hundred eighty-five".