138531029 has 16 divisors (see below), whose sum is σ = 173722752. Its totient is φ = 107535168.

The previous prime is 138531023. The next prime is 138531049. The reversal of 138531029 is 920135831.

It is not a de Polignac number, because 138531029 - 2¹² = 138526933 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138530986 and 138531004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138531023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9539 + ... + 19184.

It is an arithmetic number, because the mean of its divisors is an integer number (10857672).

Almost surely, 2^138531029 is an apocalyptic number.

It is an amenable number.

138531029 is a deficient number, since it is larger than the sum of its proper divisors (35191723).

138531029 is a wasteful number, since it uses less digits than its factorization.

138531029 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28796.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 138531029 is about 11769.9205179984. The cubic root of 138531029 is about 517.4269202194.

The spelling of 138531029 in words is "one hundred thirty-eight million, five hundred thirty-one thousand, twenty-nine".