138908 has 36 divisors (see below), whose sum is σ = 312816. Its totient is φ = 52800.

The previous prime is 138899. The next prime is 138917. The reversal of 138908 is 809831.

It is a happy number.

138908 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138899) and next prime (138917).

It is a nialpdrome in base 11.

It is a congruent number.

It is an unprimeable number.

138908 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3368 + ... + 3408.

2¹³⁸⁹⁰⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138908, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156408).

138908 is an abundant number, since it is smaller than the sum of its proper divisors (173908).

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

138908 is a wasteful number, since it uses less digits than its factorization.

138908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 138908 is about 372.7036356141. The cubic root of 138908 is about 51.7895836303.

The spelling of 138908 in words is "one hundred thirty-eight thousand, nine hundred eight".