129181385256 has 128 divisors (see below), whose sum is σ = 407494886400. Its totient is φ = 33149306880.

The previous prime is 129181385251. The next prime is 129181385279. The reversal of 129181385256 is 652583181921.

It is a junction number, because it is equal to n+sod(n) for n = 129181385199 and 129181385208.

It is not an unprimeable number, because it can be changed into a prime (129181385251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 267721 + ... + 574488.

It is an arithmetic number, because the mean of its divisors is an integer number (3183553800).

Almost surely, 2^129181385256 is an apocalyptic number.

It is an amenable number.

129181385256 is an abundant number, since it is smaller than the sum of its proper divisors (278313501144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129181385256 is a wasteful number, since it uses less digits than its factorization.

129181385256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 842319 (or 842315 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 51.

The spelling of 129181385256 in words is "one hundred twenty-nine billion, one hundred eighty-one million, three hundred eighty-five thousand, two hundred fifty-six".