6820805 has 4 divisors (see below), whose sum is σ = 8184972. Its totient is φ = 5456640.

The previous prime is 6820783. The next prime is 6820817. The reversal of 6820805 is 5080286.

It is a happy number.

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 2163841 + 4656964 = 1471^2 + 2158^2 .

It is not a de Polignac number, because 6820805 - 2⁶ = 6820741 is a prime.

It is a Duffinian number.

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, 682076 + ... + 682085.

It is an arithmetic number, because the mean of its divisors is an integer number (2046243).

Almost surely, 2^6820805 is an apocalyptic number.

It is an amenable number.

6820805 is a deficient number, since it is larger than the sum of its proper divisors (1364167).

6820805 is a wasteful number, since it uses less digits than its factorization.

6820805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1364166.

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 6820805 is about 2611.6670921080. The cubic root of 6820805 is about 189.6466655803.

The spelling of 6820805 in words is "six million, eight hundred twenty thousand, eight hundred five".