667806 has 8 divisors (see below), whose sum is σ = 1335624. Its totient is φ = 222600.

The previous prime is 667801. The next prime is 667817. The reversal of 667806 is 608766.

It is a sphenic number, since it is the product of 3 distinct primes.

667806 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667801) by changing a digit.

667806 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55645 + ... + 55656.

It is an arithmetic number, because the mean of its divisors is an integer number (166953).

2⁶⁶⁷⁸⁰⁶ is an apocalyptic number.

667806 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

667806 is a wasteful number, since it uses less digits than its factorization.

667806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111306.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 667806 is about 817.1939794198. The cubic root of 667806 is about 87.4077831182.

The spelling of 667806 in words is "six hundred sixty-seven thousand, eight hundred six".