138915 has 40 divisors (see below), whose sum is σ = 290400. Its totient is φ = 63504.

The previous prime is 138899. The next prime is 138917. The reversal of 138915 is 519831.

138915 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 138915 - 2⁴ = 138899 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

Its product of digits (1080) is a multiple of the sum of its prime divisors (15).

It is not an unprimeable number, because it can be changed into a prime (138917) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 19842 + ... + 19848.

It is an arithmetic number, because the mean of its divisors is an integer number (7260).

2¹³⁸⁹¹⁵ is an apocalyptic number.

138915 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138915 is an abundant number, since it is smaller than the sum of its proper divisors (151485).

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

138915 is an frugal number, since it uses more digits than its factorization.

138915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38 (or 15 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 138915 is about 372.7130263353. The cubic root of 138915 is about 51.7904535609.

The spelling of 138915 in words is "one hundred thirty-eight thousand, nine hundred fifteen".