138813 has 4 divisors (see below), whose sum is σ = 185088. Its totient is φ = 92540.

The previous prime is 138799. The next prime is 138821. The reversal of 138813 is 318831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 318831 = 3 ⋅106277.

It is a cyclic number.

It is not a de Polignac number, because 138813 - 2⁴ = 138797 is a prime.

It is a D-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 138813.

It is not an unprimeable number, because it can be changed into a prime (138863) 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, 23133 + ... + 23138.

It is an arithmetic number, because the mean of its divisors is an integer number (46272).

2¹³⁸⁸¹³ is an apocalyptic number.

It is an amenable number.

138813 is a deficient number, since it is larger than the sum of its proper divisors (46275).

138813 is an equidigital number, since it uses as much as digits as its factorization.

138813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46274.

The product of its digits is 576, while the sum is 24.

The square root of 138813 is about 372.5761667096. The cubic root of 138813 is about 51.7777745372. Note that the first 5 decimals are identical.

The spelling of 138813 in words is "one hundred thirty-eight thousand, eight hundred thirteen".