27611139581 has 2 divisors, whose sum is σ = 27611139582. Its totient is φ = 27611139580.

The previous prime is 27611139553. The next prime is 27611139583. The reversal of 27611139581 is 18593111672.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27611139556 + 25 = 166166^2 + 5^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27611139581 is a prime.

It is a super-2 number, since 2×27611139581² (a number of 22 digits) contains 22 as substring.

Together with 27611139583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27611139583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13805569790 + 13805569791.

It is an arithmetic number, because the mean of its divisors is an integer number (13805569791).

Almost surely, 2^27611139581 is an apocalyptic number.

It is an amenable number.

27611139581 is a deficient number, since it is larger than the sum of its proper divisors (1).

27611139581 is an equidigital number, since it uses as much as digits as its factorization.

27611139581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 44.

The spelling of 27611139581 in words is "twenty-seven billion, six hundred eleven million, one hundred thirty-nine thousand, five hundred eighty-one".