865441891 has 2 divisors, whose sum is σ = 865441892. Its totient is φ = 865441890.

The previous prime is 865441859. The next prime is 865441901. The reversal of 865441891 is 198144568.

865441891 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 not a de Polignac number, because 865441891 - 2⁵ = 865441859 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (865441391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432720945 + 432720946.

It is an arithmetic number, because the mean of its divisors is an integer number (432720946).

Almost surely, 2^865441891 is an apocalyptic number.

865441891 is a deficient number, since it is larger than the sum of its proper divisors (1).

865441891 is an equidigital number, since it uses as much as digits as its factorization.

865441891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 276480, while the sum is 46.

The square root of 865441891 is about 29418.3937528887. The cubic root of 865441891 is about 952.9701652576.

The spelling of 865441891 in words is "eight hundred sixty-five million, four hundred forty-one thousand, eight hundred ninety-one".