9989889869 has 4 divisors (see below), whose sum is σ = 10334368860. Its totient is φ = 9645410880.

The previous prime is 9989889839. The next prime is 9989889883. The reversal of 9989889869 is 9689889899.

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 2055534244 + 7934355625 = 45338^2 + 89075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9989889869 is a prime.

It is a super-2 number, since 2×9989889869² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9989889839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172239452 + ... + 172239509.

It is an arithmetic number, because the mean of its divisors is an integer number (2583592215).

Almost surely, 2^9989889869 is an apocalyptic number.

It is an amenable number.

9989889869 is a deficient number, since it is larger than the sum of its proper divisors (344478991).

9989889869 is a wasteful number, since it uses less digits than its factorization.

9989889869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344478990.

The product of its digits is 1451188224, while the sum is 83.

The square root of 9989889869 is about 99949.4365616935. The cubic root of 9989889869 is about 2153.7083913128.

The spelling of 9989889869 in words is "nine billion, nine hundred eighty-nine million, eight hundred eighty-nine thousand, eight hundred sixty-nine".