138671 has 4 divisors (see below), whose sum is σ = 149352. Its totient is φ = 127992.

The previous prime is 138661. The next prime is 138679. The reversal of 138671 is 176831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 176831 = 97 ⋅1823.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138671 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 138671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138679) 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, 5321 + ... + 5346.

It is an arithmetic number, because the mean of its divisors is an integer number (37338).

2¹³⁸⁶⁷¹ is an apocalyptic number.

138671 is a deficient number, since it is larger than the sum of its proper divisors (10681).

138671 is a wasteful number, since it uses less digits than its factorization.

138671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10680.

The product of its digits is 1008, while the sum is 26.

The square root of 138671 is about 372.3855528884. The cubic root of 138671 is about 51.7601130010.

The spelling of 138671 in words is "one hundred thirty-eight thousand, six hundred seventy-one".