28565816573 has 4 divisors (see below), whose sum is σ = 32646647520. Its totient is φ = 24484985628.

The previous prime is 28565816549. The next prime is 28565816593. The reversal of 28565816573 is 37561856582.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37561856582 = 2 ⋅18780928291.

It is a cyclic number.

It is not a de Polignac number, because 28565816573 - 2¹⁰ = 28565815549 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 (28565816593) 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, 2040415463 + ... + 2040415476.

It is an arithmetic number, because the mean of its divisors is an integer number (8161661880).

Almost surely, 2^28565816573 is an apocalyptic number.

It is an amenable number.

28565816573 is a deficient number, since it is larger than the sum of its proper divisors (4080830947).

28565816573 is an equidigital number, since it uses as much as digits as its factorization.

28565816573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080830946.

The product of its digits is 12096000, while the sum is 56.

The spelling of 28565816573 in words is "twenty-eight billion, five hundred sixty-five million, eight hundred sixteen thousand, five hundred seventy-three".