129912720 has 120 divisors (see below), whose sum is σ = 468523584. Its totient is φ = 29691648.

The previous prime is 129912703. The next prime is 129912751. The reversal of 129912720 is 27219921.

It is a tau number, because it is divible by the number of its divisors (120).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6237 + ... + 17283.

Almost surely, 2^129912720 is an apocalyptic number.

129912720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129912720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (234261792).

129912720 is an abundant number, since it is smaller than the sum of its proper divisors (338610864).

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

129912720 is a wasteful number, since it uses less digits than its factorization.

129912720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11077 (or 11064 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 129912720 is about 11397.9261271514. The cubic root of 129912720 is about 506.4663065896.

The spelling of 129912720 in words is "one hundred twenty-nine million, nine hundred twelve thousand, seven hundred twenty".