28224305 has 4 divisors (see below), whose sum is σ = 33869172. Its totient is φ = 22579440.

The previous prime is 28224293. The next prime is 28224307. The reversal of 28224305 is 50342282.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13424896 + 14799409 = 3664^2 + 3847^2 .

It is not a de Polignac number, because 28224305 - 2⁶ = 28224241 is a prime.

It is a super-2 number, since 2×28224305² = 1593222785466050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28224307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2822426 + ... + 2822435.

It is an arithmetic number, because the mean of its divisors is an integer number (8467293).

Almost surely, 2^28224305 is an apocalyptic number.

It is an amenable number.

28224305 is a deficient number, since it is larger than the sum of its proper divisors (5644867).

28224305 is an equidigital number, since it uses as much as digits as its factorization.

28224305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5644866.

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 28224305 is about 5312.6551742043. The cubic root of 28224305 is about 304.4676011664.

Adding to 28224305 its reverse (50342282), we get a palindrome (78566587).

The spelling of 28224305 in words is "twenty-eight million, two hundred twenty-four thousand, three hundred five".