138930881 has 2 divisors, whose sum is σ = 138930882. Its totient is φ = 138930880.

The previous prime is 138930877. The next prime is 138930887. The reversal of 138930881 is 188039831.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 134351281 + 4579600 = 11591^2 + 2140^2 .

It is a cyclic number.

It is not a de Polignac number, because 138930881 - 2² = 138930877 is a prime.

It is a super-2 number, since 2×138930881² = 38603579390872322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (138930887) 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, 69465440 + 69465441.

It is an arithmetic number, because the mean of its divisors is an integer number (69465441).

Almost surely, 2^138930881 is an apocalyptic number.

It is an amenable number.

138930881 is a deficient number, since it is larger than the sum of its proper divisors (1).

138930881 is an equidigital number, since it uses as much as digits as its factorization.

138930881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 138930881 is about 11786.8944595258. The cubic root of 138930881 is about 517.9242707676.

The spelling of 138930881 in words is "one hundred thirty-eight million, nine hundred thirty thousand, eight hundred eighty-one".