129055680 has 280 divisors, whose sum is σ = 495677952. Its totient is φ = 31684608.

The previous prime is 129055669. The next prime is 129055699. The reversal of 129055680 is 86550921.

It is a happy number.

129055680 is a `hidden beast` number, since 1 + 2 + 90 + 5 + 568 + 0 = 666.

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 39 ways as a sum of consecutive naturals, for example, 336769 + ... + 337151.

Almost surely, 2^129055680 is an apocalyptic number.

129055680 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 129055680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (247838976).

129055680 is an abundant number, since it is smaller than the sum of its proper divisors (366622272).

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

129055680 is a wasteful number, since it uses less digits than its factorization.

129055680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 406 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 129055680 is about 11360.2676024819. The cubic root of 129055680 is about 505.3501215445.

Subtracting from 129055680 its product of nonzero digits (21600), we obtain a triangular number (129034080 = T₁₆₀₆₄).

The spelling of 129055680 in words is "one hundred twenty-nine million, fifty-five thousand, six hundred eighty".