129381928 has 16 divisors (see below), whose sum is σ = 261252180. Its totient is φ = 59714688.

The previous prime is 129381919. The next prime is 129381947. The reversal of 129381928 is 829183921.

It can be written as a sum of positive squares in 2 ways, for example, as 127644804 + 1737124 = 11298^2 + 1318^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 621925 + ... + 622132.

Almost surely, 2^129381928 is an apocalyptic number.

It is an amenable number.

129381928 is an abundant number, since it is smaller than the sum of its proper divisors (131870252).

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

129381928 is a wasteful number, since it uses less digits than its factorization.

129381928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244076 (or 1244072 counting only the distinct ones).

The product of its digits is 62208, while the sum is 43.

The square root of 129381928 is about 11374.6177078617. The cubic root of 129381928 is about 505.7755987061.

The spelling of 129381928 in words is "one hundred twenty-nine million, three hundred eighty-one thousand, nine hundred twenty-eight".