138790591 has 2 divisors, whose sum is σ = 138790592. Its totient is φ = 138790590.

The previous prime is 138790559. The next prime is 138790621. The reversal of 138790591 is 195097831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138790591 - 2⁵ = 138790559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138790891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69395295 + 69395296.

It is an arithmetic number, because the mean of its divisors is an integer number (69395296).

Almost surely, 2^138790591 is an apocalyptic number.

138790591 is a deficient number, since it is larger than the sum of its proper divisors (1).

138790591 is an equidigital number, since it uses as much as digits as its factorization.

138790591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68040, while the sum is 43.

The square root of 138790591 is about 11780.9418553866. The cubic root of 138790591 is about 517.7498817334.

The spelling of 138790591 in words is "one hundred thirty-eight million, seven hundred ninety thousand, five hundred ninety-one".