818819 has 2 divisors, whose sum is σ = 818820. Its totient is φ = 818818.

The previous prime is 818813. The next prime is 818821. The reversal of 818819 is 918818.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-818819 is a prime.

It is a super-2 number, since 2×818819² = 1340929109522, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 818821, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (818813) 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, 409409 + 409410.

It is an arithmetic number, because the mean of its divisors is an integer number (409410).

2⁸¹⁸⁸¹⁹ is an apocalyptic number.

818819 is a deficient number, since it is larger than the sum of its proper divisors (1).

818819 is an equidigital number, since it uses as much as digits as its factorization.

818819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4608, while the sum is 35.

The square root of 818819 is about 904.8861806879. The cubic root of 818819 is about 93.5540595041.

Subtracting 818819 from its reverse (918818), we obtain a palindrome (99999).

The spelling of 818819 in words is "eight hundred eighteen thousand, eight hundred nineteen".