6821689 has 8 divisors (see below), whose sum is σ = 7812288. Its totient is φ = 5835120.

The previous prime is 6821677. The next prime is 6821693. The reversal of 6821689 is 9861286.

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

It is a cyclic number.

It is not a de Polignac number, because 6821689 - 2⁷ = 6821561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6821629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5154 + ... + 6340.

It is an arithmetic number, because the mean of its divisors is an integer number (976536).

Almost surely, 2^6821689 is an apocalyptic number.

It is an amenable number.

6821689 is a deficient number, since it is larger than the sum of its proper divisors (990599).

6821689 is a wasteful number, since it uses less digits than its factorization.

6821689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2015.

The product of its digits is 41472, while the sum is 40.

The square root of 6821689 is about 2611.8363271844. The cubic root of 6821689 is about 189.6548581817.

The spelling of 6821689 in words is "six million, eight hundred twenty-one thousand, six hundred eighty-nine".