138278 has 24 divisors (see below), whose sum is σ = 258552. Its totient is φ = 55104.

The previous prime is 138251. The next prime is 138283. The reversal of 138278 is 872831.

It is an Ulam number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 138278.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 1625 + ... + 1707.

It is an arithmetic number, because the mean of its divisors is an integer number (10773).

2¹³⁸²⁷⁸ is an apocalyptic number.

138278 is a deficient number, since it is larger than the sum of its proper divisors (120274).

138278 is a wasteful number, since it uses less digits than its factorization.

138278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116 (or 109 counting only the distinct ones).

The product of its digits is 2688, while the sum is 29.

The square root of 138278 is about 371.8574995882. The cubic root of 138278 is about 51.7111698882.

The spelling of 138278 in words is "one hundred thirty-eight thousand, two hundred seventy-eight".