28297291181 has 2 divisors, whose sum is σ = 28297291182. Its totient is φ = 28297291180.

The previous prime is 28297291097. The next prime is 28297291193. The reversal of 28297291181 is 18119279282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28269041956 + 28249225 = 168134^2 + 5315^2 .

It is a cyclic number.

It is not a de Polignac number, because 28297291181 - 2¹⁰ = 28297290157 is a prime.

It is a super-2 number, since 2×28297291181² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28297293181) 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, 14148645590 + 14148645591.

It is an arithmetic number, because the mean of its divisors is an integer number (14148645591).

Almost surely, 2^28297291181 is an apocalyptic number.

It is an amenable number.

28297291181 is a deficient number, since it is larger than the sum of its proper divisors (1).

28297291181 is an equidigital number, since it uses as much as digits as its factorization.

28297291181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 50.

The spelling of 28297291181 in words is "twenty-eight billion, two hundred ninety-seven million, two hundred ninety-one thousand, one hundred eighty-one".