6720395309 has 4 divisors (see below), whose sum is σ = 6876683616. Its totient is φ = 6564107004.

The previous prime is 6720395299. The next prime is 6720395347. The reversal of 6720395309 is 9035930276.

6720395309 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6720395309 - 2⁸ = 6720395053 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 6720395309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6720395009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78144089 + ... + 78144174.

It is an arithmetic number, because the mean of its divisors is an integer number (1719170904).

Almost surely, 2^6720395309 is an apocalyptic number.

It is an amenable number.

6720395309 is a deficient number, since it is larger than the sum of its proper divisors (156288307).

6720395309 is a wasteful number, since it uses less digits than its factorization.

6720395309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156288306.

The product of its (nonzero) digits is 306180, while the sum is 44.

The square root of 6720395309 is about 81978.0172302307. The cubic root of 6720395309 is about 1887.1145943155.

The spelling of 6720395309 in words is "six billion, seven hundred twenty million, three hundred ninety-five thousand, three hundred nine".