989838989 has 4 divisors (see below), whose sum is σ = 994161660. Its totient is φ = 985516320.

The previous prime is 989838947. The next prime is 989839051.

989838989 is nontrivially palindromic in base 10.

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 723072100 + 266766889 = 26890^2 + 16333^2 .

It is a cyclic number.

It is not a de Polignac number, because 989838989 - 2²⁴ = 973061773 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989838089) 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, 2160992 + ... + 2161449.

It is an arithmetic number, because the mean of its divisors is an integer number (248540415).

Almost surely, 2^989838989 is an apocalyptic number.

It is an amenable number.

989838989 is a deficient number, since it is larger than the sum of its proper divisors (4322671).

989838989 is a wasteful number, since it uses less digits than its factorization.

989838989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4322670.

The product of its digits is 80621568, while the sum is 71.

The square root of 989838989 is about 31461.7067083145. The cubic root of 989838989 is about 996.6014593392.

The spelling of 989838989 in words is "nine hundred eighty-nine million, eight hundred thirty-eight thousand, nine hundred eighty-nine".