856789 has 2 divisors, whose sum is σ = 856790. Its totient is φ = 856788.

The previous prime is 856787. The next prime is 856799. The reversal of 856789 is 987658.

It is a happy number.

856789 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., 476100 + 380689 = 690^2 + 617^2 .

It is a cyclic number.

It is not a de Polignac number, because 856789 - 2¹ = 856787 is a prime.

Together with 856787, it forms a pair of twin primes.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428394 + 428395.

It is an arithmetic number, because the mean of its divisors is an integer number (428395).

2⁸⁵⁶⁷⁸⁹ is an apocalyptic number.

It is an amenable number.

856789 is a deficient number, since it is larger than the sum of its proper divisors (1).

856789 is an equidigital number, since it uses as much as digits as its factorization.

856789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 43.

The square root of 856789 is about 925.6289753460. The cubic root of 856789 is about 94.9783514845.

The spelling of 856789 in words is "eight hundred fifty-six thousand, seven hundred eighty-nine".