129013956 has 18 divisors (see below), whose sum is σ = 326118702. Its totient is φ = 43004640.

The previous prime is 129013949. The next prime is 129013957. The reversal of 129013956 is 659310921.

It can be written as a sum of positive squares in only one way, i.e., 108493056 + 20520900 = 10416^2 + 4530^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 3583721 = 129013956 / (1 + 2 + 9 + 0 + 1 + 3 + 9 + 5 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 129013956.

It is not an unprimeable number, because it can be changed into a prime (129013957) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1791825 + ... + 1791896.

Almost surely, 2^129013956 is an apocalyptic number.

It is an amenable number.

129013956 is an abundant number, since it is smaller than the sum of its proper divisors (197104746).

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

129013956 is a wasteful number, since it uses less digits than its factorization.

129013956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3583731 (or 3583726 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 36.

The square root of 129013956 is about 11358.4310536271. The cubic root of 129013956 is about 505.2956553865.

The spelling of 129013956 in words is "one hundred twenty-nine million, thirteen thousand, nine hundred fifty-six".