129391517 has 8 divisors (see below), whose sum is σ = 132439296. Its totient is φ = 126356112.

The previous prime is 129391499. The next prime is 129391523. The reversal of 129391517 is 715193921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 129391517 - 2¹⁰ = 129390493 is a prime.

It is a super-2 number, since 2×129391517² = 33484329343122578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129391547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20063 + ... + 25715.

It is an arithmetic number, because the mean of its divisors is an integer number (16554912).

Almost surely, 2^129391517 is an apocalyptic number.

It is an amenable number.

129391517 is a deficient number, since it is larger than the sum of its proper divisors (3047779).

129391517 is an equidigital number, since it uses as much as digits as its factorization.

129391517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6187.

The product of its digits is 17010, while the sum is 38.

The square root of 129391517 is about 11375.0392087236. The cubic root of 129391517 is about 505.7880933991.

The spelling of 129391517 in words is "one hundred twenty-nine million, three hundred ninety-one thousand, five hundred seventeen".