670805 has 4 divisors (see below), whose sum is σ = 804972. Its totient is φ = 536640.

The previous prime is 670781. The next prime is 670811. The reversal of 670805 is 508076.

670805 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.

It can be written as a sum of positive squares in 2 ways, for example, as 209764 + 461041 = 458^2 + 679^2 .

It is not a de Polignac number, because 670805 - 2¹⁴ = 654421 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 14.

It is a congruent 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, 67076 + ... + 67085.

It is an arithmetic number, because the mean of its divisors is an integer number (201243).

2⁶⁷⁰⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

670805 is a deficient number, since it is larger than the sum of its proper divisors (134167).

670805 is a wasteful number, since it uses less digits than its factorization.

670805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134166.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 670805 is about 819.0268615864. The cubic root of 670805 is about 87.5384320968.

The spelling of 670805 in words is "six hundred seventy thousand, eight hundred five".