138135231 has 12 divisors (see below), whose sum is σ = 214877208. Its totient is φ = 85006224.

The previous prime is 138135223. The next prime is 138135241. The reversal of 138135231 is 132531831.

138135231 is a `hidden beast` number, since 138 + 1 + 3 + 523 + 1 = 666.

It is not a de Polignac number, because 138135231 - 2³ = 138135223 is a prime.

It is a super-2 number, since 2×138135231² = 38162684086846722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138135195 and 138135204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138135241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 590205 + ... + 590438.

It is an arithmetic number, because the mean of its divisors is an integer number (17906434).

Almost surely, 2^138135231 is an apocalyptic number.

138135231 is a deficient number, since it is larger than the sum of its proper divisors (76741977).

138135231 is a wasteful number, since it uses less digits than its factorization.

138135231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1180662 (or 1180659 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 138135231 is about 11753.0945286763. The cubic root of 138135231 is about 516.9336687707.

It can be divided in two parts, 13813 and 5231, that added together give a square (19044 = 138²).

The spelling of 138135231 in words is "one hundred thirty-eight million, one hundred thirty-five thousand, two hundred thirty-one".