865231 has 2 divisors, whose sum is σ = 865232. Its totient is φ = 865230.

The previous prime is 865217. The next prime is 865247. The reversal of 865231 is 132568.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 865231 - 2⁷ = 865103 is a prime.

It is a super-2 number, since 2×865231² = 1497249366722, which contains 22 as substring.

It is a plaindrome in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 865196 and 865205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (865201) 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, 432615 + 432616.

It is an arithmetic number, because the mean of its divisors is an integer number (432616).

2⁸⁶⁵²³¹ is an apocalyptic number.

865231 is a deficient number, since it is larger than the sum of its proper divisors (1).

865231 is an equidigital number, since it uses as much as digits as its factorization.

865231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

The square root of 865231 is about 930.1779399663. The cubic root of 865231 is about 95.2892752335.

Adding to 865231 its reverse (132568), we get a palindrome (997799).

The spelling of 865231 in words is "eight hundred sixty-five thousand, two hundred thirty-one".