6891735221 has 16 divisors (see below), whose sum is σ = 7904407680. Its totient is φ = 5886139200.

The previous prime is 6891735211. The next prime is 6891735229. The reversal of 6891735221 is 1225371986.

It is a cyclic number.

It is not a de Polignac number, because 6891735221 - 2¹⁰ = 6891734197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6891735229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3624371 + ... + 3626271.

It is an arithmetic number, because the mean of its divisors is an integer number (494025480).

Almost surely, 2^6891735221 is an apocalyptic number.

It is an amenable number.

6891735221 is a deficient number, since it is larger than the sum of its proper divisors (1012672459).

6891735221 is a wasteful number, since it uses less digits than its factorization.

6891735221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3484.

The product of its digits is 181440, while the sum is 44.

The square root of 6891735221 is about 83016.4755997266. The cubic root of 6891735221 is about 1903.0178468456.

The spelling of 6891735221 in words is "six billion, eight hundred ninety-one million, seven hundred thirty-five thousand, two hundred twenty-one".