138680761 has 2 divisors, whose sum is σ = 138680762. Its totient is φ = 138680760.

The previous prime is 138680749. The next prime is 138680833. The reversal of 138680761 is 167086831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138297600 + 383161 = 11760^2 + 619^2 .

It is an emirp because it is prime and its reverse (167086831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138680761 - 2¹¹ = 138678713 is a prime.

It is not a weakly prime, because it can be changed into another prime (138680561) 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, 69340380 + 69340381.

It is an arithmetic number, because the mean of its divisors is an integer number (69340381).

Almost surely, 2^138680761 is an apocalyptic number.

It is an amenable number.

138680761 is a deficient number, since it is larger than the sum of its proper divisors (1).

138680761 is an equidigital number, since it uses as much as digits as its factorization.

138680761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 138680761 is about 11776.2795907706. The cubic root of 138680761 is about 517.6132743085.

The spelling of 138680761 in words is "one hundred thirty-eight million, six hundred eighty thousand, seven hundred sixty-one".