669687 has 4 divisors (see below), whose sum is σ = 892920. Its totient is φ = 446456.

The previous prime is 669679. The next prime is 669689. The reversal of 669687 is 786966.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 669687 - 2³ = 669679 is a prime.

It is a D-number.

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 669687.

It is not an unprimeable number, because it can be changed into a prime (669689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111612 + ... + 111617.

It is an arithmetic number, because the mean of its divisors is an integer number (223230).

2⁶⁶⁹⁶⁸⁷ is an apocalyptic number.

669687 is a deficient number, since it is larger than the sum of its proper divisors (223233).

669687 is a wasteful number, since it uses less digits than its factorization.

669687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223232.

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

The square root of 669687 is about 818.3440596717. The cubic root of 669687 is about 87.4897729544.

The spelling of 669687 in words is "six hundred sixty-nine thousand, six hundred eighty-seven".