6775721 has 2 divisors, whose sum is σ = 6775722. Its totient is φ = 6775720.

The previous prime is 6775709. The next prime is 6775733. The reversal of 6775721 is 1275776.

It is a balanced prime because it is at equal distance from previous prime (6775709) and next prime (6775733).

It can be written as a sum of positive squares in only one way, i.e., 3463321 + 3312400 = 1861^2 + 1820^2 .

It is a cyclic number.

It is not a de Polignac number, because 6775721 - 2²² = 2581417 is a prime.

It is not a weakly prime, because it can be changed into another prime (6775781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3387860 + 3387861.

It is an arithmetic number, because the mean of its divisors is an integer number (3387861).

Almost surely, 2^6775721 is an apocalyptic number.

It is an amenable number.

6775721 is a deficient number, since it is larger than the sum of its proper divisors (1).

6775721 is an equidigital number, since it uses as much as digits as its factorization.

6775721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20580, while the sum is 35.

The square root of 6775721 is about 2603.0215135492. The cubic root of 6775721 is about 189.2279008507.

Subtracting from 6775721 its reverse (1275776), we obtain a palindrome (5499945).

The spelling of 6775721 in words is "six million, seven hundred seventy-five thousand, seven hundred twenty-one".