129476909 has 4 divisors (see below), whose sum is σ = 133941660. Its totient is φ = 125012160.

The previous prime is 129476839. The next prime is 129476911. The reversal of 129476909 is 909674921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 909674921 = 59 ⋅15418219.

It can be written as a sum of positive squares in 2 ways, for example, as 77492809 + 51984100 = 8803^2 + 7210^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129476909 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129476609) 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, 2232332 + ... + 2232389.

It is an arithmetic number, because the mean of its divisors is an integer number (33485415).

Almost surely, 2^129476909 is an apocalyptic number.

It is an amenable number.

129476909 is a deficient number, since it is larger than the sum of its proper divisors (4464751).

129476909 is an equidigital number, since it uses as much as digits as its factorization.

129476909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4464750.

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

The square root of 129476909 is about 11378.7920712174. The cubic root of 129476909 is about 505.8993339714.

The spelling of 129476909 in words is "one hundred twenty-nine million, four hundred seventy-six thousand, nine hundred nine".