6809645 has 4 divisors (see below), whose sum is σ = 8171580. Its totient is φ = 5447712.

The previous prime is 6809641. The next prime is 6809653. The reversal of 6809645 is 5469086.

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 1510441 + 5299204 = 1229^2 + 2302^2 .

It is a cyclic number.

It is not a de Polignac number, because 6809645 - 2² = 6809641 is a prime.

It is a super-3 number, since 3×6809645³ (a number of 21 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6809599 and 6809608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6809641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 680960 + ... + 680969.

It is an arithmetic number, because the mean of its divisors is an integer number (2042895).

Almost surely, 2^6809645 is an apocalyptic number.

It is an amenable number.

6809645 is a deficient number, since it is larger than the sum of its proper divisors (1361935).

6809645 is a wasteful number, since it uses less digits than its factorization.

6809645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1361934.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 6809645 is about 2609.5296511057. The cubic root of 6809645 is about 189.5431776912.

The spelling of 6809645 in words is "six million, eight hundred nine thousand, six hundred forty-five".