865211 has 2 divisors, whose sum is σ = 865212. Its totient is φ = 865210.

The previous prime is 865201. The next prime is 865213. The reversal of 865211 is 112568.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-865211 is a prime.

Together with 865213, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 10.

It is not a weakly prime, because it can be changed into another prime (865213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432605 + 432606.

It is an arithmetic number, because the mean of its divisors is an integer number (432606).

2⁸⁶⁵²¹¹ is an apocalyptic number.

865211 is a deficient number, since it is larger than the sum of its proper divisors (1).

865211 is an equidigital number, since it uses as much as digits as its factorization.

865211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 480, while the sum is 23.

The square root of 865211 is about 930.1671892730. The cubic root of 865211 is about 95.2885410172.

Adding to 865211 its reverse (112568), we get a palindrome (977779).

The spelling of 865211 in words is "eight hundred sixty-five thousand, two hundred eleven".