811231 has 2 divisors, whose sum is σ = 811232. Its totient is φ = 811230.

The previous prime is 811207. The next prime is 811241. The reversal of 811231 is 132118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 811231 - 2⁵ = 811199 is a prime.

It is a super-2 number, since 2×811231² = 1316191470722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (811241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405615 + 405616.

It is an arithmetic number, because the mean of its divisors is an integer number (405616).

2⁸¹¹²³¹ is an apocalyptic number.

811231 is a deficient number, since it is larger than the sum of its proper divisors (1).

811231 is an equidigital number, since it uses as much as digits as its factorization.

811231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 16.

The square root of 811231 is about 900.6836292506. The cubic root of 811231 is about 93.2641735386.

Adding to 811231 its reverse (132118), we get a palindrome (943349).

The spelling of 811231 in words is "eight hundred eleven thousand, two hundred thirty-one".