129517920 has 192 divisors, whose sum is σ = 518192640. Its totient is φ = 29597184.

The previous prime is 129517903. The next prime is 129517937. The reversal of 129517920 is 29715921.

It is an interprime number because it is at equal distance from previous prime (129517903) and next prime (129517937).

It is a super-2 number, since 2×129517920² = 33549783202252800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28099 + ... + 32381.

It is an arithmetic number, because the mean of its divisors is an integer number (2698920).

Almost surely, 2^129517920 is an apocalyptic number.

129517920 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 129517920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (259096320).

129517920 is an abundant number, since it is smaller than the sum of its proper divisors (388674720).

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

129517920 is a wasteful number, since it uses less digits than its factorization.

129517920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4314 (or 4300 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The square root of 129517920 is about 11380.5940091016. The cubic root of 129517920 is about 505.9527418148.

The spelling of 129517920 in words is "one hundred twenty-nine million, five hundred seventeen thousand, nine hundred twenty".