9727195721 has 2 divisors, whose sum is σ = 9727195722. Its totient is φ = 9727195720.

The previous prime is 9727195669. The next prime is 9727195739. The reversal of 9727195721 is 1275917279.

9727195721 = 69739² + 69740².

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4863667600 + 4863528121 = 69740^2 + 69739^2 .

It is a cyclic number.

It is not a de Polignac number, because 9727195721 - 2²⁶ = 9660086857 is a prime.

It is a super-3 number, since 3×9727195721³ (a number of 31 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 9727195721.

It is not a weakly prime, because it can be changed into another prime (9727195741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4863597860 + 4863597861.

It is an arithmetic number, because the mean of its divisors is an integer number (4863597861).

Almost surely, 2^9727195721 is an apocalyptic number.

9727195721 is the 69740-th centered square number.

It is an amenable number.

9727195721 is a deficient number, since it is larger than the sum of its proper divisors (1).

9727195721 is an equidigital number, since it uses as much as digits as its factorization.

9727195721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 555660, while the sum is 50.

The square root of 9727195721 is about 98626.5467356533. The cubic root of 9727195721 is about 2134.6624867803.

The spelling of 9727195721 in words is "nine billion, seven hundred twenty-seven million, one hundred ninety-five thousand, seven hundred twenty-one".