138388 has 12 divisors (see below), whose sum is σ = 250740. Its totient is φ = 66752.

The previous prime is 138373. The next prime is 138389. The reversal of 138388 is 883831.

It can be written as a sum of positive squares in 2 ways, for example, as 71824 + 66564 = 268^2 + 258^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138389) by changing a digit.

138388 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 3 ways as a sum of consecutive naturals, for example, 481 + ... + 712.

It is an arithmetic number, because the mean of its divisors is an integer number (20895).

2¹³⁸³⁸⁸ is an apocalyptic number.

It is an amenable number.

138388 is a deficient number, since it is larger than the sum of its proper divisors (112352).

138388 is a wasteful number, since it uses less digits than its factorization.

138388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1226 (or 1224 counting only the distinct ones).

The product of its digits is 4608, while the sum is 31.

The square root of 138388 is about 372.0053763052. The cubic root of 138388 is about 51.7248783138.

The spelling of 138388 in words is "one hundred thirty-eight thousand, three hundred eighty-eight".