2309891 has 2 divisors, whose sum is σ = 2309892. Its totient is φ = 2309890.

The previous prime is 2309869. The next prime is 2309893. The reversal of 2309891 is 1989032.

2309891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2309891 is a prime.

Together with 2309893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2309893) 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, 1154945 + 1154946.

It is an arithmetic number, because the mean of its divisors is an integer number (1154946).

2^2309891 is an apocalyptic number.

2309891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2309891 is an equidigital number, since it uses as much as digits as its factorization.

2309891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 2309891 is about 1519.8325565667. The cubic root of 2309891 is about 132.1895615910.

The spelling of 2309891 in words is "two million, three hundred nine thousand, eight hundred ninety-one".