81168129177 has 64 divisors (see below), whose sum is σ = 115279718400. Its totient is φ = 50737397760.

The previous prime is 81168129169. The next prime is 81168129193. The reversal of 81168129177 is 77192186118.

It is not a de Polignac number, because 81168129177 - 2³ = 81168129169 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81168109177) 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 in 63 ways as a sum of consecutive naturals, for example, 105549849 + ... + 105550617.

It is an arithmetic number, because the mean of its divisors is an integer number (1801245600).

Almost surely, 2^81168129177 is an apocalyptic number.

It is an amenable number.

81168129177 is a deficient number, since it is larger than the sum of its proper divisors (34111589223).

81168129177 is a wasteful number, since it uses less digits than its factorization.

81168129177 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1166.

The product of its digits is 338688, while the sum is 51.

The spelling of 81168129177 in words is "eighty-one billion, one hundred sixty-eight million, one hundred twenty-nine thousand, one hundred seventy-seven".