669855 has 8 divisors (see below), whose sum is σ = 1071792. Its totient is φ = 357248.

The previous prime is 669853. The next prime is 669857. The reversal of 669855 is 558966.

It is an interprime number because it is at equal distance from previous prime (669853) and next prime (669857).

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 669855 - 2¹ = 669853 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669855.

It is not an unprimeable number, because it can be changed into a prime (669853) 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 7 ways as a sum of consecutive naturals, for example, 22314 + ... + 22343.

It is an arithmetic number, because the mean of its divisors is an integer number (133974).

2⁶⁶⁹⁸⁵⁵ is an apocalyptic number.

669855 is a deficient number, since it is larger than the sum of its proper divisors (401937).

669855 is a wasteful number, since it uses less digits than its factorization.

669855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44665.

The product of its digits is 64800, while the sum is 39.

The square root of 669855 is about 818.4466995474. The cubic root of 669855 is about 87.4970883385.

Subtracting from 669855 its reverse (558966), we obtain a square (110889 = 333²).

The spelling of 669855 in words is "six hundred sixty-nine thousand, eight hundred fifty-five".