5279665721 has 8 divisors (see below), whose sum is σ = 5807237088. Its totient is φ = 4799694900.

The previous prime is 5279665627. The next prime is 5279665759. The reversal of 5279665721 is 1275669725.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-5279665721 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 5279665721.

It is not an unprimeable number, because it can be changed into a prime (5279665021) 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 7 ways as a sum of consecutive naturals, for example, 1982015 + ... + 1984676.

It is an arithmetic number, because the mean of its divisors is an integer number (725904636).

Almost surely, 2^5279665721 is an apocalyptic number.

It is an amenable number.

5279665721 is a deficient number, since it is larger than the sum of its proper divisors (527571367).

5279665721 is an equidigital number, since it uses as much as digits as its factorization.

5279665721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3966724 (or 3966702 counting only the distinct ones).

The product of its digits is 1587600, while the sum is 50.

The square root of 5279665721 is about 72661.3082802670. The cubic root of 5279665721 is about 1741.2807896129.

The spelling of 5279665721 in words is "five billion, two hundred seventy-nine million, six hundred sixty-five thousand, seven hundred twenty-one".