129857280 has 144 divisors (see below), whose sum is σ = 474077184. Its totient is φ = 29675520.

The previous prime is 129857279. The next prime is 129857297. The reversal of 129857280 is 82758921.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24465 + ... + 29295.

Almost surely, 2^129857280 is an apocalyptic number.

129857280 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 129857280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (237038592).

129857280 is an abundant number, since it is smaller than the sum of its proper divisors (344219904).

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

129857280 is an equidigital number, since it uses as much as digits as its factorization.

129857280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4862 (or 4848 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 42.

The square root of 129857280 is about 11395.4938462534. The cubic root of 129857280 is about 506.3942518359.

The spelling of 129857280 in words is "one hundred twenty-nine million, eight hundred fifty-seven thousand, two hundred eighty".