138531087 has 16 divisors (see below), whose sum is σ = 210238560. Its totient is φ = 90100800.

The previous prime is 138531073. The next prime is 138531089. The reversal of 138531087 is 780135831.

It is not a de Polignac number, because 138531087 - 2⁶ = 138531023 is a prime.

It is a super-3 number, since 3×138531087³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138531089) 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, 61464 + ... + 63677.

It is an arithmetic number, because the mean of its divisors is an integer number (13139910).

Almost surely, 2^138531087 is an apocalyptic number.

138531087 is a deficient number, since it is larger than the sum of its proper divisors (71707473).

138531087 is a wasteful number, since it uses less digits than its factorization.

138531087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125191 (or 125185 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 138531087 is about 11769.9229819060. The cubic root of 138531087 is about 517.4269924313.

The spelling of 138531087 in words is "one hundred thirty-eight million, five hundred thirty-one thousand, eighty-seven".