387649813 has 2 divisors, whose sum is σ = 387649814. Its totient is φ = 387649812.

The previous prime is 387649807. The next prime is 387649831. The reversal of 387649813 is 318946783.

It is a happy number.

Together with next prime (387649831) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 384238404 + 3411409 = 19602^2 + 1847^2 .

It is an emirp because it is prime and its reverse (318946783) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 387649813 - 2¹⁷ = 387518741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387649013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193824906 + 193824907.

It is an arithmetic number, because the mean of its divisors is an integer number (193824907).

Almost surely, 2^387649813 is an apocalyptic number.

It is an amenable number.

387649813 is a deficient number, since it is larger than the sum of its proper divisors (1).

387649813 is an equidigital number, since it uses as much as digits as its factorization.

387649813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 49.

The square root of 387649813 is about 19688.8245713146. The cubic root of 387649813 is about 729.1438094836.

The spelling of 387649813 in words is "three hundred eighty-seven million, six hundred forty-nine thousand, eight hundred thirteen".