818589821 has 4 divisors (see below), whose sum is σ = 935531232. Its totient is φ = 701648412.

The previous prime is 818589817. The next prime is 818589829. The reversal of 818589821 is 128985818.

It is a happy number.

818589821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 818589821 - 2² = 818589817 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 818589821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (818589829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58470695 + ... + 58470708.

It is an arithmetic number, because the mean of its divisors is an integer number (233882808).

Almost surely, 2^818589821 is an apocalyptic number.

It is an amenable number.

818589821 is a deficient number, since it is larger than the sum of its proper divisors (116941411).

818589821 is a wasteful number, since it uses less digits than its factorization.

818589821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116941410.

The product of its digits is 368640, while the sum is 50.

The square root of 818589821 is about 28611.0087378967. The cubic root of 818589821 is about 935.4533041732.

The spelling of 818589821 in words is "eight hundred eighteen million, five hundred eighty-nine thousand, eight hundred twenty-one".