9989920 has 48 divisors (see below), whose sum is σ = 24426360. Its totient is φ = 3856384.

The previous prime is 9989899. The next prime is 9989921. The reversal of 9989920 is 299899.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5779216 + 4210704 = 2404^2 + 2052^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (9989921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3564 + ... + 5716.

Almost surely, 2^9989920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9989920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12213180).

9989920 is an abundant number, since it is smaller than the sum of its proper divisors (14436440).

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

9989920 is a wasteful number, since it uses less digits than its factorization.

9989920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2197 (or 2189 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 46.

The square root of 9989920 is about 3160.6834703905. The cubic root of 9989920 is about 215.3710556613.

The spelling of 9989920 in words is "nine million, nine hundred eighty-nine thousand, nine hundred twenty".