9979928 has 32 divisors (see below), whose sum is σ = 21828000. Its totient is φ = 4275936.

The previous prime is 9979927. The next prime is 9979943. The reversal of 9979928 is 8299799.

It is a self number, because there is not a number n which added to its sum of digits gives 9979928.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9979927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 926 + ... + 4562.

It is an arithmetic number, because the mean of its divisors is an integer number (682125).

Almost surely, 2^9979928 is an apocalyptic number.

9979928 is a gapful number since it is divisible by the number (98) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9979928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10914000).

9979928 is an abundant number, since it is smaller than the sum of its proper divisors (11848072).

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

9979928 is a wasteful number, since it uses less digits than its factorization.

9979928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3664 (or 3646 counting only the distinct ones).

The product of its digits is 734832, while the sum is 53.

The square root of 9979928 is about 3159.1024041648. The cubic root of 9979928 is about 215.2992264085.

The spelling of 9979928 in words is "nine million, nine hundred seventy-nine thousand, nine hundred twenty-eight".