138556 has 24 divisors (see below), whose sum is σ = 274176. Its totient is φ = 60720.

The previous prime is 138547. The next prime is 138559. The reversal of 138556 is 655831.

138556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2035 + ... + 2101.

It is an arithmetic number, because the mean of its divisors is an integer number (11424).

2¹³⁸⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

138556 is a deficient number, since it is larger than the sum of its proper divisors (135620).

138556 is a wasteful number, since it uses less digits than its factorization.

138556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 127 counting only the distinct ones).

The product of its digits is 3600, while the sum is 28.

The square root of 138556 is about 372.2311110050. The cubic root of 138556 is about 51.7458008059.

It can be divided in two parts, 13855 and 6, that added together give a triangular number (13861 = T₁₆₆).

The spelling of 138556 in words is "one hundred thirty-eight thousand, five hundred fifty-six".