28447285 has 4 divisors (see below), whose sum is σ = 34136748. Its totient is φ = 22757824.

The previous prime is 28447283. The next prime is 28447291. The reversal of 28447285 is 58274482.

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 14853316 + 13593969 = 3854^2 + 3687^2 .

It is a cyclic number.

It is not a de Polignac number, because 28447285 - 2¹ = 28447283 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28447283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2844724 + ... + 2844733.

It is an arithmetic number, because the mean of its divisors is an integer number (8534187).

Almost surely, 2^28447285 is an apocalyptic number.

It is an amenable number.

28447285 is a deficient number, since it is larger than the sum of its proper divisors (5689463).

28447285 is an equidigital number, since it uses as much as digits as its factorization.

28447285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5689462.

The product of its digits is 143360, while the sum is 40.

The square root of 28447285 is about 5333.5996287685. The cubic root of 28447285 is about 305.2672923356.

The spelling of 28447285 in words is "twenty-eight million, four hundred forty-seven thousand, two hundred eighty-five".