6711721 has 4 divisors (see below), whose sum is σ = 6781012. Its totient is φ = 6642432.

The previous prime is 6711713. The next prime is 6711739. The reversal of 6711721 is 1271176.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3956121 + 2755600 = 1989^2 + 1660^2 .

It is a cyclic number.

It is not a de Polignac number, because 6711721 - 2³ = 6711713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6711121) 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, 34500 + ... + 34693.

It is an arithmetic number, because the mean of its divisors is an integer number (1695253).

Almost surely, 2^6711721 is an apocalyptic number.

It is an amenable number.

6711721 is a deficient number, since it is larger than the sum of its proper divisors (69291).

6711721 is an equidigital number, since it uses as much as digits as its factorization.

6711721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69290.

The product of its digits is 588, while the sum is 25.

The square root of 6711721 is about 2590.6989404406. The cubic root of 6711721 is about 188.6302317541.

Adding to 6711721 its reverse (1271176), we get a palindrome (7982897).

The spelling of 6711721 in words is "six million, seven hundred eleven thousand, seven hundred twenty-one".