28528814581 has 2 divisors, whose sum is σ = 28528814582. Its totient is φ = 28528814580.

The previous prime is 28528814579. The next prime is 28528814623. The reversal of 28528814581 is 18541882582.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17969402500 + 10559412081 = 134050^2 + 102759^2 .

It is a cyclic number.

It is not a de Polignac number, because 28528814581 - 2¹ = 28528814579 is a prime.

It is a super-2 number, since 2×28528814581² (a number of 22 digits) contains 22 as substring.

Together with 28528814579, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28528814521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14264407290 + 14264407291.

It is an arithmetic number, because the mean of its divisors is an integer number (14264407291).

Almost surely, 2^28528814581 is an apocalyptic number.

It is an amenable number.

28528814581 is a deficient number, since it is larger than the sum of its proper divisors (1).

28528814581 is an equidigital number, since it uses as much as digits as its factorization.

28528814581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1638400, while the sum is 52.

The spelling of 28528814581 in words is "twenty-eight billion, five hundred twenty-eight million, eight hundred fourteen thousand, five hundred eighty-one".