129796409 has 4 divisors (see below), whose sum is σ = 131574516. Its totient is φ = 128018304.

The previous prime is 129796397. The next prime is 129796423. The reversal of 129796409 is 904697921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38402809 + 91393600 = 6197^2 + 9560^2 .

It is a cyclic number.

It is not a de Polignac number, because 129796409 - 2²⁰ = 128747833 is a prime.

It is a super-3 number, since 3×129796409³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129796109) 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, 888944 + ... + 889089.

It is an arithmetic number, because the mean of its divisors is an integer number (32893629).

Almost surely, 2^129796409 is an apocalyptic number.

It is an amenable number.

129796409 is a deficient number, since it is larger than the sum of its proper divisors (1778107).

129796409 is an equidigital number, since it uses as much as digits as its factorization.

129796409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1778106.

The product of its (nonzero) digits is 244944, while the sum is 47.

The square root of 129796409 is about 11392.8226967683. The cubic root of 129796409 is about 506.3151148475.

The spelling of 129796409 in words is "one hundred twenty-nine million, seven hundred ninety-six thousand, four hundred nine".