9989743638 has 32 divisors (see below), whose sum is σ = 22882639104. Its totient is φ = 2848095072.

The previous prime is 9989743633. The next prime is 9989743657. The reversal of 9989743638 is 8363479899.

It is a happy number.

9989743638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×9989743638² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9989743633) 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 15 ways as a sum of consecutive naturals, for example, 235045 + ... + 274272.

It is an arithmetic number, because the mean of its divisors is an integer number (715082472).

Almost surely, 2^9989743638 is an apocalyptic number.

9989743638 is an abundant number, since it is smaller than the sum of its proper divisors (12892895466).

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

9989743638 is a wasteful number, since it uses less digits than its factorization.

9989743638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509796.

The product of its digits is 70543872, while the sum is 66.

The square root of 9989743638 is about 99948.7050341324. The cubic root of 9989743638 is about 2153.6978826728.

The spelling of 9989743638 in words is "nine billion, nine hundred eighty-nine million, seven hundred forty-three thousand, six hundred thirty-eight".