81139616127 has 12 divisors (see below), whose sum is σ = 117235209000. Its totient is φ = 54077596848.

The previous prime is 81139616111. The next prime is 81139616197. The reversal of 81139616127 is 72161693118.

81139616127 is a `hidden beast` number, since 8 + 1 + 1 + 3 + 9 + 616 + 1 + 27 = 666.

It is not a de Polignac number, because 81139616127 - 2⁴ = 81139616111 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81139616197) 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 in 11 ways as a sum of consecutive naturals, for example, 1256808 + ... + 1319789.

It is an arithmetic number, because the mean of its divisors is an integer number (9769600750).

Almost surely, 2^81139616127 is an apocalyptic number.

81139616127 is a deficient number, since it is larger than the sum of its proper divisors (36095592873).

81139616127 is a wasteful number, since it uses less digits than its factorization.

81139616127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2580102 (or 2580099 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The spelling of 81139616127 in words is "eighty-one billion, one hundred thirty-nine million, six hundred sixteen thousand, one hundred twenty-seven".