27581247997 has 2 divisors, whose sum is σ = 27581247998. Its totient is φ = 27581247996.

The previous prime is 27581247943. The next prime is 27581248063. The reversal of 27581247997 is 79974218572.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27009607716 + 571640281 = 164346^2 + 23909^2 .

It is a cyclic number.

It is not a de Polignac number, because 27581247997 - 2¹¹ = 27581245949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27581247917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13790623998 + 13790623999.

It is an arithmetic number, because the mean of its divisors is an integer number (13790623999).

Almost surely, 2^27581247997 is an apocalyptic number.

It is an amenable number.

27581247997 is a deficient number, since it is larger than the sum of its proper divisors (1).

27581247997 is an equidigital number, since it uses as much as digits as its factorization.

27581247997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17781120, while the sum is 61.

The spelling of 27581247997 in words is "twenty-seven billion, five hundred eighty-one million, two hundred forty-seven thousand, nine hundred ninety-seven".