9815920 has 40 divisors (see below), whose sum is σ = 23614560. Its totient is φ = 3790080.

The previous prime is 9815909. The next prime is 9815941. The reversal of 9815920 is 295189.

9815920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205 + ... + 4435.

It is an arithmetic number, because the mean of its divisors is an integer number (590364).

Almost surely, 2^9815920 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 9815920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11807280).

9815920 is an abundant number, since it is smaller than the sum of its proper divisors (13798640).

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

9815920 is a wasteful number, since it uses less digits than its factorization.

9815920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4273 (or 4267 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 9815920 is about 3133.0368654071. The cubic root of 9815920 is about 214.1133123378.

The spelling of 9815920 in words is "nine million, eight hundred fifteen thousand, nine hundred twenty".