129861280 has 48 divisors (see below), whose sum is σ = 307812960. Its totient is φ = 51772672.

The previous prime is 129861271. The next prime is 129861293. The reversal of 129861280 is 82168921.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54351 + ... + 56689.

It is an arithmetic number, because the mean of its divisors is an integer number (6412770).

Almost surely, 2^129861280 is an apocalyptic number.

129861280 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 129861280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153906480).

129861280 is an abundant number, since it is smaller than the sum of its proper divisors (177951680).

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

129861280 is a wasteful number, since it uses less digits than its factorization.

129861280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2701 (or 2693 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 129861280 is about 11395.6693528726. The cubic root of 129861280 is about 506.3994512779.

The spelling of 129861280 in words is "one hundred twenty-nine million, eight hundred sixty-one thousand, two hundred eighty".