129905604 has 18 divisors (see below), whose sum is σ = 328372590. Its totient is φ = 43301856.

The previous prime is 129905599. The next prime is 129905609. The reversal of 129905604 is 406509921.

129905604 is a `hidden beast` number, since 1 + 2 + 9 + 90 + 560 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (129905599) and next prime (129905609).

It can be written as a sum of positive squares in only one way, i.e., 117288900 + 12616704 = 10830^2 + 3552^2 .

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: 3608489 = 129905604 / (1 + 2 + 9 + 9 + 0 + 5 + 6 + 0 + 4).

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (129905609) 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, 1804209 + ... + 1804280.

Almost surely, 2^129905604 is an apocalyptic number.

It is an amenable number.

129905604 is an abundant number, since it is smaller than the sum of its proper divisors (198466986).

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

129905604 is a wasteful number, since it uses less digits than its factorization.

129905604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3608499 (or 3608494 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 129905604 is about 11397.6139608253. The cubic root of 129905604 is about 506.4570591501.

The spelling of 129905604 in words is "one hundred twenty-nine million, nine hundred five thousand, six hundred four".