129404950509 has 4 divisors (see below), whose sum is σ = 172539934016. Its totient is φ = 86269967004.

The previous prime is 129404950501. The next prime is 129404950547. The reversal of 129404950509 is 905059404921.

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 not a de Polignac number, because 129404950509 - 2³ = 129404950501 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 (129404950501) 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, 21567491749 + ... + 21567491754.

It is an arithmetic number, because the mean of its divisors is an integer number (43134983504).

Almost surely, 2^129404950509 is an apocalyptic number.

It is an amenable number.

129404950509 is a deficient number, since it is larger than the sum of its proper divisors (43134983507).

129404950509 is an equidigital number, since it uses as much as digits as its factorization.

129404950509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43134983506.

The product of its (nonzero) digits is 583200, while the sum is 48.

The spelling of 129404950509 in words is "one hundred twenty-nine billion, four hundred four million, nine hundred fifty thousand, five hundred nine".