28223928 has 24 divisors (see below), whose sum is σ = 76440000. Its totient is φ = 9407952.

The previous prime is 28223891. The next prime is 28223929. The reversal of 28223928 is 82932282.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×28223928² = 1593180223498368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 28223892 and 28223901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28223929) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 195928 + ... + 196071.

It is an arithmetic number, because the mean of its divisors is an integer number (3185000).

Almost surely, 2^28223928 is an apocalyptic number.

It is an amenable number.

28223928 is an abundant number, since it is smaller than the sum of its proper divisors (48216072).

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

28223928 is a wasteful number, since it uses less digits than its factorization.

28223928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392011 (or 392004 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 28223928 is about 5312.6196927693. The cubic root of 28223928 is about 304.4662455405.

It can be divided in two parts, 2822392 and 8, that added together give a square (2822400 = 1680²).

The spelling of 28223928 in words is "twenty-eight million, two hundred twenty-three thousand, nine hundred twenty-eight".