28164205 has 4 divisors (see below), whose sum is σ = 33797052. Its totient is φ = 22531360.

The previous prime is 28164197. The next prime is 28164221. The reversal of 28164205 is 50246182.

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 3849444 + 24314761 = 1962^2 + 4931^2 .

It is not a de Polignac number, because 28164205 - 2³ = 28164197 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, 2816416 + ... + 2816425.

It is an arithmetic number, because the mean of its divisors is an integer number (8449263).

Almost surely, 2^28164205 is an apocalyptic number.

It is an amenable number.

28164205 is a deficient number, since it is larger than the sum of its proper divisors (5632847).

28164205 is an equidigital number, since it uses as much as digits as its factorization.

28164205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5632846.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 28164205 is about 5306.9958545301. The cubic root of 28164205 is about 304.2513394927.

It can be divided in two parts, 2816 and 4205, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 28164205 in words is "twenty-eight million, one hundred sixty-four thousand, two hundred five".