9928421 has 8 divisors (see below), whose sum is σ = 10308864. Its totient is φ = 9555120.

The previous prime is 9928409. The next prime is 9928441. The reversal of 9928421 is 1248299.

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 9928421 - 2¹⁰ = 9927397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9928441) 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, 1136 + ... + 4598.

It is an arithmetic number, because the mean of its divisors is an integer number (1288608).

Almost surely, 2^9928421 is an apocalyptic number.

It is an amenable number.

9928421 is a deficient number, since it is larger than the sum of its proper divisors (380443).

9928421 is a wasteful number, since it uses less digits than its factorization.

9928421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3571.

The product of its digits is 10368, while the sum is 35.

The square root of 9928421 is about 3150.9397011051. The cubic root of 9928421 is about 214.9281966824.

The spelling of 9928421 in words is "nine million, nine hundred twenty-eight thousand, four hundred twenty-one".