9921604 has 24 divisors (see below), whose sum is σ = 21647808. Its totient is φ = 3865440.

The previous prime is 9921601. The next prime is 9921619. The reversal of 9921604 is 4061299.

It is a happy number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (9921601) 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, 15799 + ... + 16414.

It is an arithmetic number, because the mean of its divisors is an integer number (901992).

Almost surely, 2^9921604 is an apocalyptic number.

It is an amenable number.

9921604 is an abundant number, since it is smaller than the sum of its proper divisors (11726204).

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

9921604 is a wasteful number, since it uses less digits than its factorization.

9921604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32235 (or 32233 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 9921604 is about 3149.8577745670. The cubic root of 9921604 is about 214.8789944652.

The spelling of 9921604 in words is "nine million, nine hundred twenty-one thousand, six hundred four".