138911 has 4 divisors (see below), whose sum is σ = 143424. Its totient is φ = 134400.

The previous prime is 138899. The next prime is 138917. The reversal of 138911 is 119831.

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

It is a cyclic number.

It is not a de Polignac number, because 138911 - 2¹⁴ = 122527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 138911.

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

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2210 + ... + 2271.

It is an arithmetic number, because the mean of its divisors is an integer number (35856).

2¹³⁸⁹¹¹ is an apocalyptic number.

138911 is a deficient number, since it is larger than the sum of its proper divisors (4513).

138911 is an equidigital number, since it uses as much as digits as its factorization.

138911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4512.

The product of its digits is 216, while the sum is 23.

The square root of 138911 is about 372.7076602379. The cubic root of 138911 is about 51.7899564613.

The spelling of 138911 in words is "one hundred thirty-eight thousand, nine hundred eleven".