129908239 has 4 divisors (see below), whose sum is σ = 129976056. Its totient is φ = 129840424.

The previous prime is 129908189. The next prime is 129908257. The reversal of 129908239 is 932809921.

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 129908239 - 2¹³ = 129900047 is a prime.

It is a super-2 number, since 2×129908239² = 33752301120162242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129908195 and 129908204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129908299) 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, 30949 + ... + 34894.

It is an arithmetic number, because the mean of its divisors is an integer number (32494014).

Almost surely, 2^129908239 is an apocalyptic number.

129908239 is a deficient number, since it is larger than the sum of its proper divisors (67817).

129908239 is an equidigital number, since it uses as much as digits as its factorization.

129908239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67816.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 129908239 is about 11397.7295546087. The cubic root of 129908239 is about 506.4604834451.

The spelling of 129908239 in words is "one hundred twenty-nine million, nine hundred eight thousand, two hundred thirty-nine".