129729 has 8 divisors (see below), whose sum is σ = 175392. Its totient is φ = 85280.

The previous prime is 129719. The next prime is 129733. The reversal of 129729 is 927921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 129729 - 2¹¹ = 127681 is a prime.

It is a super-2 number, since 2×129729² = 33659226882, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 129696 and 129705.

It is not an unprimeable number, because it can be changed into a prime (129719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12 + ... + 509.

It is an arithmetic number, because the mean of its divisors is an integer number (21924).

2¹²⁹⁷²⁹ is an apocalyptic number.

It is an amenable number.

129729 is a deficient number, since it is larger than the sum of its proper divisors (45663).

129729 is an equidigital number, since it uses as much as digits as its factorization.

129729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 607.

The product of its digits is 2268, while the sum is 30.

The square root of 129729 is about 360.1791221045. The cubic root of 129729 is about 50.6227449079.

It can be divided in two parts, 1297 and 29, that added together give a triangular number (1326 = T₅₁).

The spelling of 129729 in words is "one hundred twenty-nine thousand, seven hundred twenty-nine".