820900900 has 18 divisors (see below), whose sum is σ = 1781355170. Its totient is φ = 328360320.

The previous prime is 820900891. The next prime is 820900901. The reversal of 820900900 is 9009028.

It is a happy number.

820900900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 287845156 + 533055744 = 16966^2 + 23088^2 .

It is not an unprimeable number, because it can be changed into a prime (820900901) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4104405 + ... + 4104604.

Almost surely, 2^820900900 is an apocalyptic number.

It is an amenable number.

820900900 is an abundant number, since it is smaller than the sum of its proper divisors (960454270).

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

820900900 is a wasteful number, since it uses less digits than its factorization.

820900900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8209023 (or 8209016 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 820900900 is about 28651.3682046774. The cubic root of 820900900 is about 936.3328147194.

Adding to 820900900 its reverse (9009028), we get a palindrome (829909928).

The spelling of 820900900 in words is "eight hundred twenty million, nine hundred thousand, nine hundred".