818231 has 2 divisors, whose sum is σ = 818232. Its totient is φ = 818230.

The previous prime is 818219. The next prime is 818239. The reversal of 818231 is 132818.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-818231 is a prime.

It is a super-2 number, since 2×818231² = 1339003938722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 818197 and 818206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (818239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409115 + 409116.

It is an arithmetic number, because the mean of its divisors is an integer number (409116).

2⁸¹⁸²³¹ is an apocalyptic number.

818231 is a deficient number, since it is larger than the sum of its proper divisors (1).

818231 is an equidigital number, since it uses as much as digits as its factorization.

818231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 23.

The square root of 818231 is about 904.5612195977. The cubic root of 818231 is about 93.5316601868.

The spelling of 818231 in words is "eight hundred eighteen thousand, two hundred thirty-one".