20928224 has 72 divisors (see below), whose sum is σ = 45799488. Its totient is φ = 9400320.

The previous prime is 20928223. The next prime is 20928239. The reversal of 20928224 is 42282902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20928223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 286652 + ... + 286724.

It is an arithmetic number, because the mean of its divisors is an integer number (636104).

Almost surely, 2^20928224 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 20928224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22899744).

20928224 is an abundant number, since it is smaller than the sum of its proper divisors (24871264).

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

20928224 is a wasteful number, since it uses less digits than its factorization.

20928224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 20928224 is about 4574.7375881027. The cubic root of 20928224 is about 275.5777341766.

The spelling of 20928224 in words is "twenty million, nine hundred twenty-eight thousand, two hundred twenty-four".