7947688691 has 2 divisors, whose sum is σ = 7947688692. Its totient is φ = 7947688690.

The previous prime is 7947688669. The next prime is 7947688711. The reversal of 7947688691 is 1968867497.

It is a strong prime.

It is an emirp because it is prime and its reverse (1968867497) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7947688691 - 2¹⁴ = 7947672307 is a prime.

It is not a weakly prime, because it can be changed into another prime (7947688291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3973844345 + 3973844346.

It is an arithmetic number, because the mean of its divisors is an integer number (3973844346).

Almost surely, 2^7947688691 is an apocalyptic number.

7947688691 is a deficient number, since it is larger than the sum of its proper divisors (1).

7947688691 is an equidigital number, since it uses as much as digits as its factorization.

7947688691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36578304, while the sum is 65.

The square root of 7947688691 is about 89149.8103811780. The cubic root of 7947688691 is about 1995.6311879394.

The spelling of 7947688691 in words is "seven billion, nine hundred forty-seven million, six hundred eighty-eight thousand, six hundred ninety-one".