7939664917 has 2 divisors, whose sum is σ = 7939664918. Its totient is φ = 7939664916.

The previous prime is 7939664911. The next prime is 7939664933. The reversal of 7939664917 is 7194669397.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7116778321 + 822886596 = 84361^2 + 28686^2 .

It is an emirp because it is prime and its reverse (7194669397) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7939664917 - 2¹¹ = 7939662869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7939664911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3969832458 + 3969832459.

It is an arithmetic number, because the mean of its divisors is an integer number (3969832459).

Almost surely, 2^7939664917 is an apocalyptic number.

It is an amenable number.

7939664917 is a deficient number, since it is larger than the sum of its proper divisors (1).

7939664917 is an equidigital number, since it uses as much as digits as its factorization.

7939664917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15431472, while the sum is 61.

The square root of 7939664917 is about 89104.7973848771. The cubic root of 7939664917 is about 1994.9593831803.

The spelling of 7939664917 in words is "seven billion, nine hundred thirty-nine million, six hundred sixty-four thousand, nine hundred seventeen".