129821128 has 16 divisors (see below), whose sum is σ = 249076080. Its totient is φ = 63400848.

The previous prime is 129821113. The next prime is 129821141. The reversal of 129821128 is 821128921.

It is a junction number, because it is equal to n+sod(n) for n = 129821093 and 129821102.

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, 188350 + ... + 189037.

It is an arithmetic number, because the mean of its divisors is an integer number (15567255).

Almost surely, 2^129821128 is an apocalyptic number.

It is an amenable number.

129821128 is a deficient number, since it is larger than the sum of its proper divisors (119254952).

129821128 is a wasteful number, since it uses less digits than its factorization.

129821128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377436 (or 377432 counting only the distinct ones).

The product of its digits is 4608, while the sum is 34.

The square root of 129821128 is about 11393.9074947974. The cubic root of 129821128 is about 506.3472544344.

The spelling of 129821128 in words is "one hundred twenty-nine million, eight hundred twenty-one thousand, one hundred twenty-eight".