129366321 has 12 divisors (see below), whose sum is σ = 200650032. Its totient is φ = 73923528.

The previous prime is 129366271. The next prime is 129366337. The reversal of 129366321 is 123663921.

It is not a de Polignac number, because 129366321 - 2⁶ = 129366257 is a prime.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (129365321) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 439875 + ... + 440168.

It is an arithmetic number, because the mean of its divisors is an integer number (16720836).

Almost surely, 2^129366321 is an apocalyptic number.

It is an amenable number.

129366321 is a deficient number, since it is larger than the sum of its proper divisors (71283711).

129366321 is an equidigital number, since it uses as much as digits as its factorization.

129366321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880060 (or 880053 counting only the distinct ones).

The product of its digits is 11664, while the sum is 33.

The square root of 129366321 is about 11373.9316421368. The cubic root of 129366321 is about 505.7552610972.

The spelling of 129366321 in words is "one hundred twenty-nine million, three hundred sixty-six thousand, three hundred twenty-one".