866857 has 2 divisors, whose sum is σ = 866858. Its totient is φ = 866856.

The previous prime is 866851. The next prime is 866869. The reversal of 866857 is 758668.

866857 is nontrivially palindromic in base 3.

866857 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., 477481 + 389376 = 691^2 + 624^2 .

It is a cyclic number.

It is not a de Polignac number, because 866857 - 2³ = 866849 is a prime.

It is not a weakly prime, because it can be changed into another prime (866851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433428 + 433429.

It is an arithmetic number, because the mean of its divisors is an integer number (433429).

2⁸⁶⁶⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

866857 is a deficient number, since it is larger than the sum of its proper divisors (1).

866857 is an equidigital number, since it uses as much as digits as its factorization.

866857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 40.

The square root of 866857 is about 931.0515560376. The cubic root of 866857 is about 95.3489292083.

The spelling of 866857 in words is "eight hundred sixty-six thousand, eight hundred fifty-seven".