856841 has 2 divisors, whose sum is σ = 856842. Its totient is φ = 856840.

The previous prime is 856831. The next prime is 856847. The reversal of 856841 is 148658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 606841 + 250000 = 779^2 + 500^2 .

It is a cyclic number.

It is not a de Polignac number, because 856841 - 2¹⁴ = 840457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 856798 and 856807.

It is not a weakly prime, because it can be changed into another prime (856847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428420 + 428421.

It is an arithmetic number, because the mean of its divisors is an integer number (428421).

2⁸⁵⁶⁸⁴¹ is an apocalyptic number.

It is an amenable number.

856841 is a deficient number, since it is larger than the sum of its proper divisors (1).

856841 is an equidigital number, since it uses as much as digits as its factorization.

856841 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7680, while the sum is 32.

The square root of 856841 is about 925.6570639281. The cubic root of 856841 is about 94.9802729122.

The spelling of 856841 in words is "eight hundred fifty-six thousand, eight hundred forty-one".