129392639 has 4 divisors (see below), whose sum is σ = 130602024. Its totient is φ = 128183256.

The previous prime is 129392629. The next prime is 129392699. The reversal of 129392639 is 936293921.

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

It is a cyclic number.

It is not a de Polignac number, because 129392639 - 2⁴ = 129392623 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129392639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129392629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 604532 + ... + 604745.

It is an arithmetic number, because the mean of its divisors is an integer number (32650506).

Almost surely, 2^129392639 is an apocalyptic number.

129392639 is a deficient number, since it is larger than the sum of its proper divisors (1209385).

129392639 is a wasteful number, since it uses less digits than its factorization.

129392639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209384.

The product of its digits is 157464, while the sum is 44.

The square root of 129392639 is about 11375.0885271280. The cubic root of 129392639 is about 505.7895553512.

It can be divided in two parts, 129392 and 639, that added together give a palindrome (130031).

The spelling of 129392639 in words is "one hundred twenty-nine million, three hundred ninety-two thousand, six hundred thirty-nine".