989935021 has 4 divisors (see below), whose sum is σ = 995064412. Its totient is φ = 984805632.

The previous prime is 989934971. The next prime is 989935027. The reversal of 989935021 is 120539989.

989935021 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.

It can be written as a sum of positive squares in 2 ways, for example, as 620757225 + 369177796 = 24915^2 + 19214^2 .

It is a cyclic number.

It is not a de Polignac number, because 989935021 - 2²⁷ = 855717293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989935027) 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, 2564406 + ... + 2564791.

It is an arithmetic number, because the mean of its divisors is an integer number (248766103).

Almost surely, 2^989935021 is an apocalyptic number.

It is an amenable number.

989935021 is a deficient number, since it is larger than the sum of its proper divisors (5129391).

989935021 is a wasteful number, since it uses less digits than its factorization.

989935021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5129390.

The product of its (nonzero) digits is 174960, while the sum is 46.

The square root of 989935021 is about 31463.2328440674. The cubic root of 989935021 is about 996.6336876570.

The spelling of 989935021 in words is "nine hundred eighty-nine million, nine hundred thirty-five thousand, twenty-one".