138155 has 4 divisors (see below), whose sum is σ = 165792. Its totient is φ = 110520.

The previous prime is 138143. The next prime is 138157. The reversal of 138155 is 551831.

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

It is not a de Polignac number, because 138155 - 2⁴ = 138139 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138155.

It is not an unprimeable number, because it can be changed into a prime (138157) 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, 13811 + ... + 13820.

It is an arithmetic number, because the mean of its divisors is an integer number (41448).

2¹³⁸¹⁵⁵ is an apocalyptic number.

138155 is a deficient number, since it is larger than the sum of its proper divisors (27637).

138155 is an equidigital number, since it uses as much as digits as its factorization.

138155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27636.

The product of its digits is 600, while the sum is 23.

The square root of 138155 is about 371.6920768593. The cubic root of 138155 is about 51.6958327636.

Adding to 138155 its reverse (551831), we get a palindrome (689986).

The spelling of 138155 in words is "one hundred thirty-eight thousand, one hundred fifty-five".