138192121 has 2 divisors, whose sum is σ = 138192122. Its totient is φ = 138192120.

The previous prime is 138192097. The next prime is 138192157. The reversal of 138192121 is 121291831.

138192121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 134444025 + 3748096 = 11595^2 + 1936^2 .

It is a cyclic number.

It is not a de Polignac number, because 138192121 - 2¹⁹ = 137667833 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138192121.

It is not a weakly prime, because it can be changed into another prime (138192191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69096060 + 69096061.

It is an arithmetic number, because the mean of its divisors is an integer number (69096061).

Almost surely, 2^138192121 is an apocalyptic number.

It is an amenable number.

138192121 is a deficient number, since it is larger than the sum of its proper divisors (1).

138192121 is an equidigital number, since it uses as much as digits as its factorization.

138192121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 28.

The square root of 138192121 is about 11755.5144932070. The cubic root of 138192121 is about 517.0046241669.

The spelling of 138192121 in words is "one hundred thirty-eight million, one hundred ninety-two thousand, one hundred twenty-one".