855691 has 4 divisors (see below), whose sum is σ = 857752. Its totient is φ = 853632.

The previous prime is 855683. The next prime is 855697. The reversal of 855691 is 196558.

855691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 855691 - 2³ = 855683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855697) 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, 165 + ... + 1318.

It is an arithmetic number, because the mean of its divisors is an integer number (214438).

2⁸⁵⁵⁶⁹¹ is an apocalyptic number.

855691 is a deficient number, since it is larger than the sum of its proper divisors (2061).

855691 is a wasteful number, since it uses less digits than its factorization.

855691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2060.

The product of its digits is 10800, while the sum is 34.

The square root of 855691 is about 925.0356749877. The cubic root of 855691 is about 94.9377616348.

It can be divided in two parts, 85 and 5691, that added together give a square (5776 = 76²).

The spelling of 855691 in words is "eight hundred fifty-five thousand, six hundred ninety-one".