129668329 has 4 divisors (see below), whose sum is σ = 148192384. Its totient is φ = 111144276.

The previous prime is 129668323. The next prime is 129668353. The reversal of 129668329 is 923866921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 129668329 - 2³ = 129668321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129668321) 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, 9262017 + ... + 9262030.

It is an arithmetic number, because the mean of its divisors is an integer number (37048096).

Almost surely, 2^129668329 is an apocalyptic number.

It is an amenable number.

129668329 is a deficient number, since it is larger than the sum of its proper divisors (18524055).

129668329 is an equidigital number, since it uses as much as digits as its factorization.

129668329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18524054.

The product of its digits is 279936, while the sum is 46.

The square root of 129668329 is about 11387.2002265702. The cubic root of 129668329 is about 506.1485201460.

The spelling of 129668329 in words is "one hundred twenty-nine million, six hundred sixty-eight thousand, three hundred twenty-nine".