818444689 has 2 divisors, whose sum is σ = 818444690. Its totient is φ = 818444688.

The previous prime is 818444687. The next prime is 818444723. The reversal of 818444689 is 986444818.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 537312400 + 281132289 = 23180^2 + 16767^2 .

It is a cyclic number.

It is not a de Polignac number, because 818444689 - 2¹ = 818444687 is a prime.

Together with 818444687, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (818444687) 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, 409222344 + 409222345.

It is an arithmetic number, because the mean of its divisors is an integer number (409222345).

Almost surely, 2^818444689 is an apocalyptic number.

It is an amenable number.

818444689 is a deficient number, since it is larger than the sum of its proper divisors (1).

818444689 is an equidigital number, since it uses as much as digits as its factorization.

818444689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1769472, while the sum is 52.

The square root of 818444689 is about 28608.4723290147. The cubic root of 818444689 is about 935.3980171296.

The spelling of 818444689 in words is "eight hundred eighteen million, four hundred forty-four thousand, six hundred eighty-nine".