129042756 has 72 divisors (see below), whose sum is σ = 347649120. Its totient is φ = 40241664.

The previous prime is 129042731. The next prime is 129042763. The reversal of 129042756 is 657240921.

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

It is a self number, because there is not a number n which added to its sum of digits gives 129042756.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55636 + ... + 57908.

It is an arithmetic number, because the mean of its divisors is an integer number (4828460).

Almost surely, 2^129042756 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129042756, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173824560).

129042756 is an abundant number, since it is smaller than the sum of its proper divisors (218606364).

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

129042756 is a wasteful number, since it uses less digits than its factorization.

129042756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2385 (or 2380 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 129042756 is about 11359.6987636116. The cubic root of 129042756 is about 505.3332519189. Note that the first 3 decimals are identical.

The spelling of 129042756 in words is "one hundred twenty-nine million, forty-two thousand, seven hundred fifty-six".