28163928 has 64 divisors (see below), whose sum is σ = 79833600. Its totient is φ = 8208000.

The previous prime is 28163897. The next prime is 28163929. The reversal of 28163928 is 82936182.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28163929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3553 + ... + 8303.

It is an arithmetic number, because the mean of its divisors is an integer number (1247400).

Almost surely, 2^28163928 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 28163928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39916800).

28163928 is an abundant number, since it is smaller than the sum of its proper divisors (51669672).

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

28163928 is a wasteful number, since it uses less digits than its factorization.

28163928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4792 (or 4788 counting only the distinct ones).

The product of its digits is 41472, while the sum is 39.

The square root of 28163928 is about 5306.9697568386. The cubic root of 28163928 is about 304.2503420340.

The spelling of 28163928 in words is "twenty-eight million, one hundred sixty-three thousand, nine hundred twenty-eight".