129171209617 has 4 divisors (see below), whose sum is σ = 132175191280. Its totient is φ = 126167227956.

The previous prime is 129171209533. The next prime is 129171209659. The reversal of 129171209617 is 716902171921.

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 a de Polignac number, because none of the positive numbers 2^k-129171209617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129171299617) 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, 1501990767 + ... + 1501990852.

It is an arithmetic number, because the mean of its divisors is an integer number (33043797820).

Almost surely, 2^129171209617 is an apocalyptic number.

It is an amenable number.

129171209617 is a deficient number, since it is larger than the sum of its proper divisors (3003981663).

129171209617 is an equidigital number, since it uses as much as digits as its factorization.

129171209617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3003981662.

The product of its (nonzero) digits is 95256, while the sum is 46.

The spelling of 129171209617 in words is "one hundred twenty-nine billion, one hundred seventy-one million, two hundred nine thousand, six hundred seventeen".