387866138509 has 2 divisors, whose sum is σ = 387866138510. Its totient is φ = 387866138508.

The previous prime is 387866138501. The next prime is 387866138579. The reversal of 387866138509 is 905831668783.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 252258076009 + 135608062500 = 502253^2 + 368250^2 .

It is an emirp because it is prime and its reverse (905831668783) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 387866138509 - 2³ = 387866138501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387866138501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193933069254 + 193933069255.

It is an arithmetic number, because the mean of its divisors is an integer number (193933069255).

Almost surely, 2^387866138509 is an apocalyptic number.

It is an amenable number.

387866138509 is a deficient number, since it is larger than the sum of its proper divisors (1).

387866138509 is an equidigital number, since it uses as much as digits as its factorization.

387866138509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52254720, while the sum is 64.

The spelling of 387866138509 in words is "three hundred eighty-seven billion, eight hundred sixty-six million, one hundred thirty-eight thousand, five hundred nine".