28897565 has 4 divisors (see below), whose sum is σ = 34677084. Its totient is φ = 23118048.

The previous prime is 28897511. The next prime is 28897571. The reversal of 28897565 is 56579882.

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 9721924 + 19175641 = 3118^2 + 4379^2 .

It is a cyclic number.

It is not a de Polignac number, because 28897565 - 2¹⁶ = 28832029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2889752 + ... + 2889761.

It is an arithmetic number, because the mean of its divisors is an integer number (8669271).

Almost surely, 2^28897565 is an apocalyptic number.

It is an amenable number.

28897565 is a deficient number, since it is larger than the sum of its proper divisors (5779519).

28897565 is an equidigital number, since it uses as much as digits as its factorization.

28897565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5779518.

The product of its digits is 1209600, while the sum is 50.

The square root of 28897565 is about 5375.6455426302. The cubic root of 28897565 is about 306.8695169938.

The spelling of 28897565 in words is "twenty-eight million, eight hundred ninety-seven thousand, five hundred sixty-five".