384516721 has 2 divisors, whose sum is σ = 384516722. Its totient is φ = 384516720.

The previous prime is 384516703. The next prime is 384516731. The reversal of 384516721 is 127615483.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 274266721 + 110250000 = 16561^2 + 10500^2 .

It is a cyclic number.

It is not a de Polignac number, because 384516721 - 2¹¹ = 384514673 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (384516731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 192258360 + 192258361.

It is an arithmetic number, because the mean of its divisors is an integer number (192258361).

Almost surely, 2^384516721 is an apocalyptic number.

It is an amenable number.

384516721 is a deficient number, since it is larger than the sum of its proper divisors (1).

384516721 is an equidigital number, since it uses as much as digits as its factorization.

384516721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 37.

The square root of 384516721 is about 19609.0979139786. The cubic root of 384516721 is about 727.1741133578.

The spelling of 384516721 in words is "three hundred eighty-four million, five hundred sixteen thousand, seven hundred twenty-one".