138564 has 24 divisors (see below), whose sum is σ = 359520. Its totient is φ = 46152.

The previous prime is 138563. The next prime is 138569. The reversal of 138564 is 465831.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (138563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 534 + ... + 749.

It is an arithmetic number, because the mean of its divisors is an integer number (14980).

2¹³⁸⁵⁶⁴ is an apocalyptic number.

It is an amenable number.

138564 is an abundant number, since it is smaller than the sum of its proper divisors (220956).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138564 is a wasteful number, since it uses less digits than its factorization.

138564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1296 (or 1288 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 138564 is about 372.2418568619. The cubic root of 138564 is about 51.7467966931.

The spelling of 138564 in words is "one hundred thirty-eight thousand, five hundred sixty-four".