9928639 has 8 divisors (see below), whose sum is σ = 11368448. Its totient is φ = 8494200.

The previous prime is 9928619. The next prime is 9928661. The reversal of 9928639 is 9368299.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9928639 - 2¹³ = 9920447 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9928619) 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 7 ways as a sum of consecutive naturals, for example, 4114 + ... + 6064.

It is an arithmetic number, because the mean of its divisors is an integer number (1421056).

Almost surely, 2^9928639 is an apocalyptic number.

9928639 is a deficient number, since it is larger than the sum of its proper divisors (1439809).

9928639 is a wasteful number, since it uses less digits than its factorization.

9928639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2685.

The product of its digits is 209952, while the sum is 46.

The square root of 9928639 is about 3150.9742937701. The cubic root of 9928639 is about 214.9297697423.

The spelling of 9928639 in words is "nine million, nine hundred twenty-eight thousand, six hundred thirty-nine".