387544021 has 2 divisors, whose sum is σ = 387544022. Its totient is φ = 387544020.

The previous prime is 387543991. The next prime is 387544039. The reversal of 387544021 is 120445783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 255040900 + 132503121 = 15970^2 + 11511^2 .

It is an emirp because it is prime and its reverse (120445783) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 387544021 - 2¹³ = 387535829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387544621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193772010 + 193772011.

It is an arithmetic number, because the mean of its divisors is an integer number (193772011).

Almost surely, 2^387544021 is an apocalyptic number.

It is an amenable number.

387544021 is a deficient number, since it is larger than the sum of its proper divisors (1).

387544021 is an equidigital number, since it uses as much as digits as its factorization.

387544021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 387544021 is about 19686.1377877937. The cubic root of 387544021 is about 729.0774741835.

The spelling of 387544021 in words is "three hundred eighty-seven million, five hundred forty-four thousand, twenty-one".