138955 has 4 divisors (see below), whose sum is σ = 166752. Its totient is φ = 111160.

The previous prime is 138937. The next prime is 138959. The reversal of 138955 is 559831.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138955 - 2⁵ = 138923 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (138959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13891 + ... + 13900.

It is an arithmetic number, because the mean of its divisors is an integer number (41688).

2¹³⁸⁹⁵⁵ is an apocalyptic number.

138955 is a deficient number, since it is larger than the sum of its proper divisors (27797).

138955 is an equidigital number, since it uses as much as digits as its factorization.

138955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27796.

The product of its digits is 5400, while the sum is 31.

The square root of 138955 is about 372.7666830606. The cubic root of 138955 is about 51.7954240329.

It can be divided in two parts, 1389 and 55, that added together give a square (1444 = 38²).

The spelling of 138955 in words is "one hundred thirty-eight thousand, nine hundred fifty-five".