129283920 has 240 divisors, whose sum is σ = 467505792. Its totient is φ = 31933440.

The previous prime is 129283901. The next prime is 129283951. The reversal of 129283920 is 29382921.

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 a congruent number.

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, 612615 + ... + 612825.

Almost surely, 2^129283920 is an apocalyptic number.

129283920 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 129283920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (233752896).

129283920 is an abundant number, since it is smaller than the sum of its proper divisors (338221872).

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

129283920 is a wasteful number, since it uses less digits than its factorization.

129283920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290 (or 281 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 129283920 is about 11370.3087029333. The cubic root of 129283920 is about 505.6478565567.

Subtracting from 129283920 its reverse (29382921), we obtain a palindrome (99900999).

The spelling of 129283920 in words is "one hundred twenty-nine million, two hundred eighty-three thousand, nine hundred twenty".