669867 has 16 divisors (see below), whose sum is σ = 995328. Its totient is φ = 397280.

The previous prime is 669863. The next prime is 669869. The reversal of 669867 is 768966.

It is a happy number.

669867 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 669867 - 2² = 669863 is a prime.

669867 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669867.

It is not an unprimeable number, because it can be changed into a prime (669863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1558 + ... + 1940.

It is an arithmetic number, because the mean of its divisors is an integer number (62208).

2⁶⁶⁹⁸⁶⁷ is an apocalyptic number.

669867 is a deficient number, since it is larger than the sum of its proper divisors (325461).

669867 is a wasteful number, since it uses less digits than its factorization.

669867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450.

The product of its digits is 108864, while the sum is 42.

The square root of 669867 is about 818.4540304745. The cubic root of 669867 is about 87.4976108191.

Subtracting 669867 from its reverse (768966), we obtain a palindrome (99099).

The spelling of 669867 in words is "six hundred sixty-nine thousand, eight hundred sixty-seven".