859891 has 2 divisors, whose sum is σ = 859892. Its totient is φ = 859890.

The previous prime is 859861. The next prime is 859913. The reversal of 859891 is 198958.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-859891 is a prime.

It is not a weakly prime, because it can be changed into another prime (859801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 429945 + 429946.

It is an arithmetic number, because the mean of its divisors is an integer number (429946).

2⁸⁵⁹⁸⁹¹ is an apocalyptic number.

859891 is a deficient number, since it is larger than the sum of its proper divisors (1).

859891 is an equidigital number, since it uses as much as digits as its factorization.

859891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 40.

The square root of 859891 is about 927.3030788259. The cubic root of 859891 is about 95.0928363030.

The spelling of 859891 in words is "eight hundred fifty-nine thousand, eight hundred ninety-one".