138521529 has 32 divisors (see below), whose sum is σ = 209139840. Its totient is φ = 90602496.

The previous prime is 138521527. The next prime is 138521563. The reversal of 138521529 is 925125831.

It is not a de Polignac number, because 138521529 - 2¹ = 138521527 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138521493 and 138521502.

It is not an unprimeable number, because it can be changed into a prime (138521521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 594397 + ... + 594629.

It is an arithmetic number, because the mean of its divisors is an integer number (6535620).

Almost surely, 2^138521529 is an apocalyptic number.

It is an amenable number.

138521529 is a deficient number, since it is larger than the sum of its proper divisors (70618311).

138521529 is a wasteful number, since it uses less digits than its factorization.

138521529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 560 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 138521529 is about 11769.5169399598. The cubic root of 138521529 is about 517.4150921398.

The spelling of 138521529 in words is "one hundred thirty-eight million, five hundred twenty-one thousand, five hundred twenty-nine".