3111685921 has 4 divisors (see below), whose sum is σ = 3118436244. Its totient is φ = 3104935600.

The previous prime is 3111685909. The next prime is 3111685937. The reversal of 3111685921 is 1295861113.

3111685921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2288282896 + 823403025 = 47836^2 + 28695^2 .

It is a cyclic number.

It is not a de Polignac number, because 3111685921 - 2¹¹ = 3111683873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3111605921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3374470 + ... + 3375391.

It is an arithmetic number, because the mean of its divisors is an integer number (779609061).

Almost surely, 2^3111685921 is an apocalyptic number.

It is an amenable number.

3111685921 is a deficient number, since it is larger than the sum of its proper divisors (6750323).

3111685921 is an equidigital number, since it uses as much as digits as its factorization.

3111685921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6750322.

The product of its digits is 12960, while the sum is 37.

The square root of 3111685921 is about 55782.4875834701. The cubic root of 3111685921 is about 1459.9296145777.

The spelling of 3111685921 in words is "three billion, one hundred eleven million, six hundred eighty-five thousand, nine hundred twenty-one".