6691885 has 4 divisors (see below), whose sum is σ = 8030268. Its totient is φ = 5353504.

The previous prime is 6691859. The next prime is 6691891. The reversal of 6691885 is 5881966.

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 2244004 + 4447881 = 1498^2 + 2109^2 .

It is a cyclic number.

It is not a de Polignac number, because 6691885 - 2¹⁹ = 6167597 is a prime.

It is a Duffinian number.

6691885 is a lucky number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 669184 + ... + 669193.

It is an arithmetic number, because the mean of its divisors is an integer number (2007567).

Almost surely, 2^6691885 is an apocalyptic number.

It is an amenable number.

6691885 is a deficient number, since it is larger than the sum of its proper divisors (1338383).

6691885 is a wasteful number, since it uses less digits than its factorization.

6691885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338382.

The product of its digits is 103680, while the sum is 43.

The square root of 6691885 is about 2586.8677971632. The cubic root of 6691885 is about 188.4442207733. Note that the first 3 decimals are identical.

The spelling of 6691885 in words is "six million, six hundred ninety-one thousand, eight hundred eighty-five".