6244391721 has 16 divisors (see below), whose sum is σ = 8604343808. Its totient is φ = 4023993600.

The previous prime is 6244391719. The next prime is 6244391723. The reversal of 6244391721 is 1271934426.

6244391721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6244391719) and next prime (6244391723).

It is not a de Polignac number, because 6244391721 - 2¹ = 6244391719 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6244391721.

It is not an unprimeable number, because it can be changed into a prime (6244391723) 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 in 15 ways as a sum of consecutive naturals, for example, 43281 + ... + 119841.

It is an arithmetic number, because the mean of its divisors is an integer number (537771488).

Almost surely, 2^6244391721 is an apocalyptic number.

It is an amenable number.

6244391721 is a deficient number, since it is larger than the sum of its proper divisors (2359952087).

6244391721 is a wasteful number, since it uses less digits than its factorization.

6244391721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77472.

The product of its digits is 72576, while the sum is 39.

The square root of 6244391721 is about 79021.4636728528. The cubic root of 6244391721 is about 1841.4646224010.

The spelling of 6244391721 in words is "six billion, two hundred forty-four million, three hundred ninety-one thousand, seven hundred twenty-one".