129725517 has 8 divisors (see below), whose sum is σ = 177186240. Its totient is φ = 84374240.

The previous prime is 129725473. The next prime is 129725549. The reversal of 129725517 is 715527921.

It is a happy number.

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 129725517 - 2¹² = 129721421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129721517) 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 7 ways as a sum of consecutive naturals, for example, 527217 + ... + 527462.

It is an arithmetic number, because the mean of its divisors is an integer number (22148280).

Almost surely, 2^129725517 is an apocalyptic number.

It is an amenable number.

129725517 is a deficient number, since it is larger than the sum of its proper divisors (47460723).

129725517 is a wasteful number, since it uses less digits than its factorization.

129725517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054723.

The product of its digits is 44100, while the sum is 39.

The square root of 129725517 is about 11389.7110147712. The cubic root of 129725517 is about 506.2229185940. Note that the first 3 decimals are identical.

The spelling of 129725517 in words is "one hundred twenty-nine million, seven hundred twenty-five thousand, five hundred seventeen".