129255447 has 4 divisors (see below), whose sum is σ = 172340600. Its totient is φ = 86170296.

The previous prime is 129255419. The next prime is 129255481. The reversal of 129255447 is 744552921.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 129255447 - 2⁶ = 129255383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129245447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21542572 + ... + 21542577.

It is an arithmetic number, because the mean of its divisors is an integer number (43085150).

Almost surely, 2^129255447 is an apocalyptic number.

129255447 is a deficient number, since it is larger than the sum of its proper divisors (43085153).

129255447 is an equidigital number, since it uses as much as digits as its factorization.

129255447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43085152.

The product of its digits is 100800, while the sum is 39.

The square root of 129255447 is about 11369.0565571643. The cubic root of 129255447 is about 505.6107331762.

The spelling of 129255447 in words is "one hundred twenty-nine million, two hundred fifty-five thousand, four hundred forty-seven".