138261 has 8 divisors (see below), whose sum is σ = 195264. Its totient is φ = 86720.

The previous prime is 138251. The next prime is 138283. The reversal of 138261 is 162831.

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

It is a cyclic number.

It is not a de Polignac number, because 138261 - 2⁶ = 138197 is a prime.

It is a super-2 number, since 2×138261² = 38232208242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138241) 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 7 ways as a sum of consecutive naturals, for example, 1305 + ... + 1406.

It is an arithmetic number, because the mean of its divisors is an integer number (24408).

2¹³⁸²⁶¹ is an apocalyptic number.

It is an amenable number.

138261 is a deficient number, since it is larger than the sum of its proper divisors (57003).

138261 is a wasteful number, since it uses less digits than its factorization.

138261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2731.

The product of its digits is 288, while the sum is 21.

The square root of 138261 is about 371.8346406671. The cubic root of 138261 is about 51.7090506648.

The spelling of 138261 in words is "one hundred thirty-eight thousand, two hundred sixty-one".