3109921 has 2 divisors, whose sum is σ = 3109922. Its totient is φ = 3109920.

The previous prime is 3109913. The next prime is 3109937. The reversal of 3109921 is 1299013.

3109921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3097600 + 12321 = 1760^2 + 111^2 .

It is an emirp because it is prime and its reverse (1299013) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3109921 - 2³ = 3109913 is a prime.

It is not a weakly prime, because it can be changed into another prime (3109121) 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 as a sum of consecutive naturals, namely, 1554960 + 1554961.

It is an arithmetic number, because the mean of its divisors is an integer number (1554961).

Almost surely, 2^3109921 is an apocalyptic number.

It is an amenable number.

3109921 is a deficient number, since it is larger than the sum of its proper divisors (1).

3109921 is an equidigital number, since it uses as much as digits as its factorization.

3109921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 25.

The square root of 3109921 is about 1763.4968103175. The cubic root of 3109921 is about 145.9653542612.

The spelling of 3109921 in words is "three million, one hundred nine thousand, nine hundred twenty-one".