129631968 has 96 divisors (see below), whose sum is σ = 384652800. Its totient is φ = 42461568.

The previous prime is 129631961. The next prime is 129631981. The reversal of 129631968 is 869136921.

It is a happy number.

129631968 is a `hidden beast` number, since 1 + 2 + 9 + 631 + 9 + 6 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129631961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49705 + ... + 52247.

It is an arithmetic number, because the mean of its divisors is an integer number (4006800).

Almost surely, 2^129631968 is an apocalyptic number.

129631968 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 129631968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192326400).

129631968 is an abundant number, since it is smaller than the sum of its proper divisors (255020832).

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

129631968 is a wasteful number, since it uses less digits than its factorization.

129631968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2621 (or 2607 counting only the distinct ones).

The product of its digits is 139968, while the sum is 45.

The square root of 129631968 is about 11385.6035413148. The cubic root of 129631968 is about 506.1012051051.

The spelling of 129631968 in words is "one hundred twenty-nine million, six hundred thirty-one thousand, nine hundred sixty-eight".