129643920 has 240 divisors, whose sum is σ = 515324160. Its totient is φ = 28578816.

The previous prime is 129643901. The next prime is 129643933. The reversal of 129643920 is 29346921.

129643920 is a `hidden beast` number, since 1 + 2 + 9 + 643 + 9 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 145717 + ... + 146603.

It is an arithmetic number, because the mean of its divisors is an integer number (2147184).

Almost surely, 2^129643920 is an apocalyptic number.

129643920 is a gapful number since it is divisible by the number (10) 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 129643920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (257662080).

129643920 is an abundant number, since it is smaller than the sum of its proper divisors (385680240).

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

129643920 is a wasteful number, since it uses less digits than its factorization.

129643920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942 (or 933 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 129643920 is about 11386.1284025783. The cubic root of 129643920 is about 506.1167587164.

The spelling of 129643920 in words is "one hundred twenty-nine million, six hundred forty-three thousand, nine hundred twenty".