138090817 has 2 divisors, whose sum is σ = 138090818. Its totient is φ = 138090816.

The previous prime is 138090793. The next prime is 138090839. The reversal of 138090817 is 718090831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114896961 + 23193856 = 10719^2 + 4816^2 .

It is an emirp because it is prime and its reverse (718090831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138090817 - 2¹⁵ = 138058049 is a prime.

It is not a weakly prime, because it can be changed into another prime (138090877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69045408 + 69045409.

It is an arithmetic number, because the mean of its divisors is an integer number (69045409).

Almost surely, 2^138090817 is an apocalyptic number.

It is an amenable number.

138090817 is a deficient number, since it is larger than the sum of its proper divisors (1).

138090817 is an equidigital number, since it uses as much as digits as its factorization.

138090817 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 37.

The square root of 138090817 is about 11751.2049169436. The cubic root of 138090817 is about 516.8782603788.

The spelling of 138090817 in words is "one hundred thirty-eight million, ninety thousand, eight hundred seventeen".