28561522331 has 2 divisors, whose sum is σ = 28561522332. Its totient is φ = 28561522330.

The previous prime is 28561522313. The next prime is 28561522391. The reversal of 28561522331 is 13322516582.

Together with previous prime (28561522313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28561522331 is a prime.

It is a super-2 number, since 2×28561522331² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28561522391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14280761165 + 14280761166.

It is an arithmetic number, because the mean of its divisors is an integer number (14280761166).

Almost surely, 2^28561522331 is an apocalyptic number.

28561522331 is a deficient number, since it is larger than the sum of its proper divisors (1).

28561522331 is an equidigital number, since it uses as much as digits as its factorization.

28561522331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86400, while the sum is 38.

The spelling of 28561522331 in words is "twenty-eight billion, five hundred sixty-one million, five hundred twenty-two thousand, three hundred thirty-one".