384432721 has 2 divisors, whose sum is σ = 384432722. Its totient is φ = 384432720.

The previous prime is 384432707. The next prime is 384432743. The reversal of 384432721 is 127234483.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 255360400 + 129072321 = 15980^2 + 11361^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-384432721 is a prime.

It is not a weakly prime, because it can be changed into another prime (384432761) 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, 192216360 + 192216361.

It is an arithmetic number, because the mean of its divisors is an integer number (192216361).

Almost surely, 2^384432721 is an apocalyptic number.

It is an amenable number.

384432721 is a deficient number, since it is larger than the sum of its proper divisors (1).

384432721 is an equidigital number, since it uses as much as digits as its factorization.

384432721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 34.

The square root of 384432721 is about 19606.9559340556. The cubic root of 384432721 is about 727.1211576425.

The spelling of 384432721 in words is "three hundred eighty-four million, four hundred thirty-two thousand, seven hundred twenty-one".