129920380 has 24 divisors (see below), whose sum is σ = 281635200. Its totient is φ = 50291520.

The previous prime is 129920359. The next prime is 129920383. The reversal of 129920380 is 83029921.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129920383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104155 + ... + 105394.

It is an arithmetic number, because the mean of its divisors is an integer number (11734800).

Almost surely, 2^129920380 is an apocalyptic number.

129920380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129920380 is an abundant number, since it is smaller than the sum of its proper divisors (151714820).

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

129920380 is a wasteful number, since it uses less digits than its factorization.

129920380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209589 (or 209587 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 129920380 is about 11398.2621482400. The cubic root of 129920380 is about 506.4762605947.

The spelling of 129920380 in words is "one hundred twenty-nine million, nine hundred twenty thousand, three hundred eighty".