138539587 has 4 divisors (see below), whose sum is σ = 138647376. Its totient is φ = 138431800.

The previous prime is 138539563. The next prime is 138539617. The reversal of 138539587 is 785935831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138539587 - 2⁷ = 138539459 is a prime.

It is a super-2 number, since 2×138539587² = 38386434332261138, which contains 22 as substring.

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 138539587.

It is not an unprimeable number, because it can be changed into a prime (138579587) 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 3 ways as a sum of consecutive naturals, for example, 51943 + ... + 54544.

It is an arithmetic number, because the mean of its divisors is an integer number (34661844).

Almost surely, 2^138539587 is an apocalyptic number.

138539587 is a deficient number, since it is larger than the sum of its proper divisors (107789).

138539587 is a wasteful number, since it uses less digits than its factorization.

138539587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107788.

The product of its digits is 907200, while the sum is 49.

The square root of 138539587 is about 11770.2840662407. The cubic root of 138539587 is about 517.4375749886.

The spelling of 138539587 in words is "one hundred thirty-eight million, five hundred thirty-nine thousand, five hundred eighty-seven".