820888939 has 12 divisors (see below), whose sum is σ = 935679000. Its totient is φ = 717859584.

The previous prime is 820888933. The next prime is 820888949. The reversal of 820888939 is 939888028.

It is not a de Polignac number, because 820888939 - 2⁵ = 820888907 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 820888939.

It is not an unprimeable number, because it can be changed into a prime (820888933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 124614 + ... + 131035.

It is an arithmetic number, because the mean of its divisors is an integer number (77973250).

Almost surely, 2^820888939 is an apocalyptic number.

820888939 is a deficient number, since it is larger than the sum of its proper divisors (114790061).

820888939 is a wasteful number, since it uses less digits than its factorization.

820888939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255694 (or 255681 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 55.

The square root of 820888939 is about 28651.1594704298. The cubic root of 820888939 is about 936.3282670608.

The spelling of 820888939 in words is "eight hundred twenty million, eight hundred eighty-eight thousand, nine hundred thirty-nine".