856171 has 4 divisors (see below), whose sum is σ = 906552. Its totient is φ = 805792.

The previous prime is 856169. The next prime is 856181. The reversal of 856171 is 171658.

856171 = T₇₅₄ + T₇₅₅ + T₇₅₆.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 171658 = 2 ⋅85829.

It is a cyclic number.

It is not a de Polignac number, because 856171 - 2¹ = 856169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (856111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25165 + ... + 25198.

It is an arithmetic number, because the mean of its divisors is an integer number (226638).

2⁸⁵⁶¹⁷¹ is an apocalyptic number.

856171 is the 756-th centered triangular number.

856171 is a deficient number, since it is larger than the sum of its proper divisors (50381).

856171 is a wasteful number, since it uses less digits than its factorization.

856171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50380.

The product of its digits is 1680, while the sum is 28.

The square root of 856171 is about 925.2950880665. The cubic root of 856171 is about 94.9555101006.

The spelling of 856171 in words is "eight hundred fifty-six thousand, one hundred seventy-one".