138568189 has 2 divisors, whose sum is σ = 138568190. Its totient is φ = 138568188.

The previous prime is 138568187. The next prime is 138568201. The reversal of 138568189 is 981865831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105884100 + 32684089 = 10290^2 + 5717^2 .

It is a cyclic number.

It is not a de Polignac number, because 138568189 - 2¹ = 138568187 is a prime.

It is a super-2 number, since 2×138568189² = 38402286005479442, which contains 22 as substring.

Together with 138568187, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138568181) 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, 69284094 + 69284095.

It is an arithmetic number, because the mean of its divisors is an integer number (69284095).

Almost surely, 2^138568189 is an apocalyptic number.

It is an amenable number.

138568189 is a deficient number, since it is larger than the sum of its proper divisors (1).

138568189 is an equidigital number, since it uses as much as digits as its factorization.

138568189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 414720, while the sum is 49.

The square root of 138568189 is about 11771.4990124453. The cubic root of 138568189 is about 517.4731814927.

The spelling of 138568189 in words is "one hundred thirty-eight million, five hundred sixty-eight thousand, one hundred eighty-nine".