129006721 has 8 divisors (see below), whose sum is σ = 129929184. Its totient is φ = 128088000.

The previous prime is 129006719. The next prime is 129006737. The reversal of 129006721 is 127600921.

It is a happy number.

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 129006721 - 2¹ = 129006719 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 129006721.

It is not an unprimeable number, because it can be changed into a prime (129006791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108090 + ... + 109276.

It is an arithmetic number, because the mean of its divisors is an integer number (16241148).

Almost surely, 2^129006721 is an apocalyptic number.

It is an amenable number.

129006721 is a deficient number, since it is larger than the sum of its proper divisors (922463).

129006721 is a wasteful number, since it uses less digits than its factorization.

129006721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1871.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 129006721 is about 11358.1125632739. The cubic root of 129006721 is about 505.2862096838.

The spelling of 129006721 in words is "one hundred twenty-nine million, six thousand, seven hundred twenty-one".