28320775481 has 4 divisors (see below), whose sum is σ = 28413025872. Its totient is φ = 28228525092.

The previous prime is 28320775453. The next prime is 28320775519. The reversal of 28320775481 is 18457702382.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28320775481 is a prime.

It is a super-2 number, since 2×28320775481² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28320775421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46124735 + ... + 46125348.

It is an arithmetic number, because the mean of its divisors is an integer number (7103256468).

Almost surely, 2^28320775481 is an apocalyptic number.

It is an amenable number.

28320775481 is a deficient number, since it is larger than the sum of its proper divisors (92250391).

28320775481 is an equidigital number, since it uses as much as digits as its factorization.

28320775481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92250390.

The product of its (nonzero) digits is 752640, while the sum is 47.

The spelling of 28320775481 in words is "twenty-eight billion, three hundred twenty million, seven hundred seventy-five thousand, four hundred eighty-one".