138258881 has 2 divisors, whose sum is σ = 138258882. Its totient is φ = 138258880.

The previous prime is 138258833. The next prime is 138258907. The reversal of 138258881 is 188852831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 132618256 + 5640625 = 11516^2 + 2375^2 .

It is a cyclic number.

It is not a de Polignac number, because 138258881 - 2⁶ = 138258817 is a prime.

It is a super-2 number, since 2×138258881² = 38231036350744322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138258811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69129440 + 69129441.

It is an arithmetic number, because the mean of its divisors is an integer number (69129441).

Almost surely, 2^138258881 is an apocalyptic number.

It is an amenable number.

138258881 is a deficient number, since it is larger than the sum of its proper divisors (1).

138258881 is an equidigital number, since it uses as much as digits as its factorization.

138258881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122880, while the sum is 44.

The square root of 138258881 is about 11758.3536687752. The cubic root of 138258881 is about 517.0878649766.

The spelling of 138258881 in words is "one hundred thirty-eight million, two hundred fifty-eight thousand, eight hundred eighty-one".