129493728 has 336 divisors, whose sum is σ = 478156896. Its totient is φ = 33592320.

The previous prime is 129493697. The next prime is 129493753. The reversal of 129493728 is 827394921.

It is a tau number, because it is divible by the number of its divisors (336).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 2122818 + ... + 2122878.

It is an arithmetic number, because the mean of its divisors is an integer number (1423086).

Almost surely, 2^129493728 is an apocalyptic number.

129493728 is a gapful number since it is divisible by the number (18) 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 129493728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (239078448).

129493728 is an abundant number, since it is smaller than the sum of its proper divisors (348663168).

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

129493728 is an equidigital number, since it uses as much as digits as its factorization.

129493728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 86 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 129493728 is about 11379.5310975453. The cubic root of 129493728 is about 505.9212383984.

The spelling of 129493728 in words is "one hundred twenty-nine million, four hundred ninety-three thousand, seven hundred twenty-eight".