129525839 has 4 divisors (see below), whose sum is σ = 137145024. Its totient is φ = 121906656.

The previous prime is 129525821. The next prime is 129525841. The reversal of 129525839 is 938525921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 938525921 = 59 ⋅15907219.

It is a cyclic number.

It is not a de Polignac number, because 129525839 - 2²⁰ = 128477263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129525839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129525859) 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, 3809567 + ... + 3809600.

It is an arithmetic number, because the mean of its divisors is an integer number (34286256).

Almost surely, 2^129525839 is an apocalyptic number.

129525839 is a deficient number, since it is larger than the sum of its proper divisors (7619185).

129525839 is an equidigital number, since it uses as much as digits as its factorization.

129525839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7619184.

The product of its digits is 194400, while the sum is 44.

The square root of 129525839 is about 11380.9419205969. The cubic root of 129525839 is about 505.9630532788.

The spelling of 129525839 in words is "one hundred twenty-nine million, five hundred twenty-five thousand, eight hundred thirty-nine".