28225805 has 4 divisors (see below), whose sum is σ = 33870972. Its totient is φ = 22580640.

The previous prime is 28225793. The next prime is 28225817. The reversal of 28225805 is 50852282.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (28225793) and next prime (28225817).

It can be written as a sum of positive squares in 2 ways, for example, as 17656804 + 10569001 = 4202^2 + 3251^2 .

It is not a de Polignac number, because 28225805 - 2⁶ = 28225741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2822576 + ... + 2822585.

It is an arithmetic number, because the mean of its divisors is an integer number (8467743).

Almost surely, 2^28225805 is an apocalyptic number.

It is an amenable number.

28225805 is a deficient number, since it is larger than the sum of its proper divisors (5645167).

28225805 is an equidigital number, since it uses as much as digits as its factorization.

28225805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5645166.

The product of its (nonzero) digits is 12800, while the sum is 32.

The square root of 28225805 is about 5312.7963446757. The cubic root of 28225805 is about 304.4729947838.

The spelling of 28225805 in words is "twenty-eight million, two hundred twenty-five thousand, eight hundred five".