129689520 has 40 divisors (see below), whose sum is σ = 402038256. Its totient is φ = 34583808.

The previous prime is 129689513. The next prime is 129689531. The reversal of 129689520 is 25986921.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269947 + ... + 270426.

Almost surely, 2^129689520 is an apocalyptic number.

129689520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129689520 is an abundant number, since it is smaller than the sum of its proper divisors (272348736).

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

129689520 is a wasteful number, since it uses less digits than its factorization.

129689520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540389 (or 540383 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 129689520 is about 11388.1306631071. The cubic root of 129689520 is about 506.1760910241.

The spelling of 129689520 in words is "one hundred twenty-nine million, six hundred eighty-nine thousand, five hundred twenty".