6168072721 has 2 divisors, whose sum is σ = 6168072722. Its totient is φ = 6168072720.

The previous prime is 6168072709. The next prime is 6168072751. The reversal of 6168072721 is 1272708616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6156756225 + 11316496 = 78465^2 + 3364^2 .

It is a cyclic number.

It is not a de Polignac number, because 6168072721 - 2¹¹ = 6168070673 is a prime.

It is not a weakly prime, because it can be changed into another prime (6168072751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3084036360 + 3084036361.

It is an arithmetic number, because the mean of its divisors is an integer number (3084036361).

Almost surely, 2^6168072721 is an apocalyptic number.

It is an amenable number.

6168072721 is a deficient number, since it is larger than the sum of its proper divisors (1).

6168072721 is an equidigital number, since it uses as much as digits as its factorization.

6168072721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 6168072721 is about 78537.0786380548. The cubic root of 6168072721 is about 1833.9317182319.

The spelling of 6168072721 in words is "six billion, one hundred sixty-eight million, seventy-two thousand, seven hundred twenty-one".