138678 has 16 divisors (see below), whose sum is σ = 287280. Its totient is φ = 44576.

The previous prime is 138661. The next prime is 138679. The reversal of 138678 is 876831.

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 (138679) 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, 225 + ... + 572.

It is an arithmetic number, because the mean of its divisors is an integer number (17955).

2¹³⁸⁶⁷⁸ is an apocalyptic number.

138678 is an abundant number, since it is smaller than the sum of its proper divisors (148602).

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

138678 is a wasteful number, since it uses less digits than its factorization.

138678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 831.

The product of its digits is 8064, while the sum is 33.

The square root of 138678 is about 372.3949516307. The cubic root of 138678 is about 51.7609839226.

The spelling of 138678 in words is "one hundred thirty-eight thousand, six hundred seventy-eight".