138684 has 48 divisors (see below), whose sum is σ = 401408. Its totient is φ = 36288.

The previous prime is 138683. The next prime is 138727. The reversal of 138684 is 486831.

It is a happy number.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1029 + ... + 1155.

2¹³⁸⁶⁸⁴ is an apocalyptic number.

138684 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138684, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200704).

138684 is an abundant number, since it is smaller than the sum of its proper divisors (262724).

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

138684 is a wasteful number, since it uses less digits than its factorization.

138684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 152 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 138684 is about 372.4030075067. The cubic root of 138684 is about 51.7617304034.

The spelling of 138684 in words is "one hundred thirty-eight thousand, six hundred eighty-four".