129781169535168 has 1008 divisors, whose sum is σ = 430127205580800. Its totient is φ = 38645343959040.

The previous prime is 129781169535113. The next prime is 129781169535191. The reversal of 129781169535168 is 861535961187921.

It is a happy number.

129781169535168 is a `hidden beast` number, since 1 + 2 + 9 + 7 + 8 + 1 + 16 + 95 + 3 + 516 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 129781169535096 and 129781169535105.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 15844357953 + ... + 15844366143.

It is an arithmetic number, because the mean of its divisors is an integer number (426713497600).

Almost surely, 2^{129781169535168} is an apocalyptic number.

129781169535168 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129781169535168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (215063602790400).

129781169535168 is an abundant number, since it is smaller than the sum of its proper divisors (300346036045632).

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

129781169535168 is an equidigital number, since it uses as much as digits as its factorization.

129781169535168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8352 (or 8287 counting only the distinct ones).

The product of its digits is 195955200, while the sum is 72.

The spelling of 129781169535168 in words is "one hundred twenty-nine trillion, seven hundred eighty-one billion, one hundred sixty-nine million, five hundred thirty-five thousand, one hundred sixty-eight".