138549 has 4 divisors (see below), whose sum is σ = 184736. Its totient is φ = 92364.

The previous prime is 138547. The next prime is 138559. The reversal of 138549 is 945831.

138549 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 138549 - 2¹ = 138547 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138547) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23089 + ... + 23094.

It is an arithmetic number, because the mean of its divisors is an integer number (46184).

2¹³⁸⁵⁴⁹ is an apocalyptic number.

It is an amenable number.

138549 is a deficient number, since it is larger than the sum of its proper divisors (46187).

138549 is an equidigital number, since it uses as much as digits as its factorization.

138549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46186.

The product of its digits is 4320, while the sum is 30.

The square root of 138549 is about 372.2217081257. The cubic root of 138549 is about 51.7449293732.

The spelling of 138549 in words is "one hundred thirty-eight thousand, five hundred forty-nine".