129487920 has 40 divisors (see below), whose sum is σ = 401413296. Its totient is φ = 34530048.

The previous prime is 129487913. The next prime is 129487951. The reversal of 129487920 is 29784921.

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

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269527 + ... + 270006.

Almost surely, 2^129487920 is an apocalyptic number.

129487920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129487920 is an abundant number, since it is smaller than the sum of its proper divisors (271925376).

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

129487920 is a wasteful number, since it uses less digits than its factorization.

129487920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539549 (or 539543 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 129487920 is about 11379.2758996344. The cubic root of 129487920 is about 505.9136744942.

The spelling of 129487920 in words is "one hundred twenty-nine million, four hundred eighty-seven thousand, nine hundred twenty".