138481 has 8 divisors (see below), whose sum is σ = 161024. Its totient is φ = 116640.

The previous prime is 138469. The next prime is 138493. The reversal of 138481 is 184831.

138481 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138469) and next prime (138493).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 6-Lehmer number, since φ(138481) divides (138481-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 138481 - 2⁵ = 138449 is a prime.

It is a super-2 number, since 2×138481² = 38353974722, which contains 22 as substring.

It is a deceptive number, since it divides R₁₃₈₄₈₀.

It is a Duffinian number.

138481 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 376 + ... + 646.

It is an arithmetic number, because the mean of its divisors is an integer number (20128).

2¹³⁸⁴⁸¹ is an apocalyptic number.

It is an amenable number.

138481 is a deficient number, since it is larger than the sum of its proper divisors (22543).

138481 is an equidigital number, since it uses as much as digits as its factorization.

138481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351.

The product of its digits is 768, while the sum is 25.

The square root of 138481 is about 372.1303535053. The cubic root of 138481 is about 51.7364624986.

The spelling of 138481 in words is "one hundred thirty-eight thousand, four hundred eighty-one".