28297295281 has 2 divisors, whose sum is σ = 28297295282. Its totient is φ = 28297295280.

The previous prime is 28297295263. The next prime is 28297295291. The reversal of 28297295281 is 18259279282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28294267681 + 3027600 = 168209^2 + 1740^2 .

It is a cyclic number.

It is not a de Polignac number, because 28297295281 - 2⁵ = 28297295249 is a prime.

It is a super-2 number, since 2×28297295281² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28297295291) 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, 14148647640 + 14148647641.

It is an arithmetic number, because the mean of its divisors is an integer number (14148647641).

Almost surely, 2^28297295281 is an apocalyptic number.

It is an amenable number.

28297295281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28297295281 is an equidigital number, since it uses as much as digits as its factorization.

28297295281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2903040, while the sum is 55.

It can be divided in two parts, 2829 and 7295281, that added together give a triangular number (7298110 = T₃₈₂₀).

The spelling of 28297295281 in words is "twenty-eight billion, two hundred ninety-seven million, two hundred ninety-five thousand, two hundred eighty-one".