27156124981 has 2 divisors, whose sum is σ = 27156124982. Its totient is φ = 27156124980.

The previous prime is 27156124979. The next prime is 27156125011. The reversal of 27156124981 is 18942165172.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16993468881 + 10162656100 = 130359^2 + 100810^2 .

It is a cyclic number.

It is not a de Polignac number, because 27156124981 - 2¹ = 27156124979 is a prime.

It is a super-3 number, since 3×27156124981³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 27156124979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27156124781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13578062490 + 13578062491.

It is an arithmetic number, because the mean of its divisors is an integer number (13578062491).

Almost surely, 2^27156124981 is an apocalyptic number.

It is an amenable number.

27156124981 is a deficient number, since it is larger than the sum of its proper divisors (1).

27156124981 is an equidigital number, since it uses as much as digits as its factorization.

27156124981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 46.

The spelling of 27156124981 in words is "twenty-seven billion, one hundred fifty-six million, one hundred twenty-four thousand, nine hundred eighty-one".