129781193280 has 672 divisors, whose sum is σ = 471226896000. Its totient is φ = 30072766464.

The previous prime is 129781193273. The next prime is 129781193291. The reversal of 129781193280 is 82391187921.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 871014646 + ... + 871014794.

It is an arithmetic number, because the mean of its divisors is an integer number (701230500).

Almost surely, 2^129781193280 is an apocalyptic number.

129781193280 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 129781193280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235613448000).

129781193280 is an abundant number, since it is smaller than the sum of its proper divisors (341445702720).

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

129781193280 is a wasteful number, since it uses less digits than its factorization.

129781193280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 51.

The spelling of 129781193280 in words is "one hundred twenty-nine billion, seven hundred eighty-one million, one hundred ninety-three thousand, two hundred eighty".