129905579 has 4 divisors (see below), whose sum is σ = 129941184. Its totient is φ = 129869976.

The previous prime is 129905519. The next prime is 129905599. The reversal of 129905579 is 975509921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 975509921 = 37 ⋅26365133.

It is a cyclic number.

It is not a de Polignac number, because 129905579 - 2⁸ = 129905323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129905519) 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, 11612 + ... + 19865.

It is an arithmetic number, because the mean of its divisors is an integer number (32485296).

Almost surely, 2^129905579 is an apocalyptic number.

129905579 is a deficient number, since it is larger than the sum of its proper divisors (35605).

129905579 is an equidigital number, since it uses as much as digits as its factorization.

129905579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35604.

The product of its (nonzero) digits is 255150, while the sum is 47.

The square root of 129905579 is about 11397.6128641045. The cubic root of 129905579 is about 506.4570266613.

The spelling of 129905579 in words is "one hundred twenty-nine million, nine hundred five thousand, five hundred seventy-nine".