820389828 has 144 divisors (see below), whose sum is σ = 2150668800. Its totient is φ = 242956800.

The previous prime is 820389827. The next prime is 820389833. The reversal of 820389828 is 828983028.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820389821) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5505898 + ... + 5506046.

It is an arithmetic number, because the mean of its divisors is an integer number (14935200).

Almost surely, 2^820389828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 820389828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1075334400).

820389828 is an abundant number, since it is smaller than the sum of its proper divisors (1330278972).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

820389828 is a wasteful number, since it uses less digits than its factorization.

820389828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 245 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 48.

The square root of 820389828 is about 28642.4480099031. The cubic root of 820389828 is about 936.1384620571.

The spelling of 820389828 in words is "eight hundred twenty million, three hundred eighty-nine thousand, eight hundred twenty-eight".