129831820 has 24 divisors (see below), whose sum is σ = 273045024. Its totient is φ = 51856896.

The previous prime is 129831817. The next prime is 129831833. The reversal of 129831820 is 28138921.

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, 10492 + ... + 19228.

It is an arithmetic number, because the mean of its divisors is an integer number (11376876).

Almost surely, 2^129831820 is an apocalyptic number.

129831820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129831820 is an abundant number, since it is smaller than the sum of its proper divisors (143213204).

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

129831820 is a wasteful number, since it uses less digits than its factorization.

129831820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9489 (or 9487 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 129831820 is about 11394.3766832592. The cubic root of 129831820 is about 506.3611548842.

The spelling of 129831820 in words is "one hundred twenty-nine million, eight hundred thirty-one thousand, eight hundred twenty".