129722909 has 4 divisors (see below), whose sum is σ = 130216416. Its totient is φ = 129229404.

The previous prime is 129722897. The next prime is 129722917. The reversal of 129722909 is 909227921.

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 129722909 - 2²⁰ = 128674333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129722969) 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 3 ways as a sum of consecutive naturals, for example, 246359 + ... + 246884.

It is an arithmetic number, because the mean of its divisors is an integer number (32554104).

Almost surely, 2^129722909 is an apocalyptic number.

It is an amenable number.

129722909 is a deficient number, since it is larger than the sum of its proper divisors (493507).

129722909 is an equidigital number, since it uses as much as digits as its factorization.

129722909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 493506.

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 129722909 is about 11389.5965248994. The cubic root of 129722909 is about 506.2195262051.

The spelling of 129722909 in words is "one hundred twenty-nine million, seven hundred twenty-two thousand, nine hundred nine".