138870191 has 2 divisors, whose sum is σ = 138870192. Its totient is φ = 138870190.

The previous prime is 138870167. The next prime is 138870197. The reversal of 138870191 is 191078831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138870191 - 2¹⁰ = 138869167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138870197) 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 as a sum of consecutive naturals, namely, 69435095 + 69435096.

It is an arithmetic number, because the mean of its divisors is an integer number (69435096).

Almost surely, 2^138870191 is an apocalyptic number.

138870191 is a deficient number, since it is larger than the sum of its proper divisors (1).

138870191 is an equidigital number, since it uses as much as digits as its factorization.

138870191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 38.

The square root of 138870191 is about 11784.3197088334. The cubic root of 138870191 is about 517.8488438074.

The spelling of 138870191 in words is "one hundred thirty-eight million, eight hundred seventy thousand, one hundred ninety-one".