28566909841 has 4 divisors (see below), whose sum is σ = 28621741284. Its totient is φ = 28512078400.

The previous prime is 28566909829. The next prime is 28566909869. The reversal of 28566909841 is 14890966582.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14890966582 = 2 ⋅7445483291.

It can be written as a sum of positive squares in 2 ways, for example, as 5970807441 + 22596102400 = 77271^2 + 150320^2 .

It is a cyclic number.

It is not a de Polignac number, because 28566909841 - 2¹⁹ = 28566385553 is a prime.

It is a super-3 number, since 3×28566909841³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28566904841) 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, 27414940 + ... + 27415981.

It is an arithmetic number, because the mean of its divisors is an integer number (7155435321).

Almost surely, 2^28566909841 is an apocalyptic number.

It is an amenable number.

28566909841 is a deficient number, since it is larger than the sum of its proper divisors (54831443).

28566909841 is an equidigital number, since it uses as much as digits as its factorization.

28566909841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54831442.

The product of its (nonzero) digits is 7464960, while the sum is 58.

The spelling of 28566909841 in words is "twenty-eight billion, five hundred sixty-six million, nine hundred nine thousand, eight hundred forty-one".