138321 has 16 divisors (see below), whose sum is σ = 211200. Its totient is φ = 89424.

The previous prime is 138319. The next prime is 138323. The reversal of 138321 is 123831.

It is an interprime number because it is at equal distance from previous prime (138319) and next prime (138323).

It is not a de Polignac number, because 138321 - 2¹ = 138319 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138294 and 138303.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 138321.

It is not an unprimeable number, because it can be changed into a prime (138323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1215 + ... + 1323.

It is an arithmetic number, because the mean of its divisors is an integer number (13200).

2¹³⁸³²¹ is an apocalyptic number.

It is an amenable number.

138321 is a deficient number, since it is larger than the sum of its proper divisors (72879).

138321 is a wasteful number, since it uses less digits than its factorization.

138321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 159 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 138321 is about 371.9153129410. The cubic root of 138321 is about 51.7165295016.

The spelling of 138321 in words is "one hundred thirty-eight thousand, three hundred twenty-one".