821120028 has 24 divisors (see below), whose sum is σ = 1921999632. Its totient is φ = 272841984.

The previous prime is 821120011. The next prime is 821120057. The reversal of 821120028 is 820021128.

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 104125 + ... + 111732.

It is an arithmetic number, because the mean of its divisors is an integer number (80083318).

Almost surely, 2^821120028 is an apocalyptic number.

It is an amenable number.

821120028 is an abundant number, since it is smaller than the sum of its proper divisors (1100879604).

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

821120028 is a wasteful number, since it uses less digits than its factorization.

821120028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216181 (or 216179 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 821120028 is about 28655.1919902834. The cubic root of 821120028 is about 936.4161209518.

The spelling of 821120028 in words is "eight hundred twenty-one million, one hundred twenty thousand, twenty-eight".