9661684691 has 2 divisors, whose sum is σ = 9661684692. Its totient is φ = 9661684690.

The previous prime is 9661684679. The next prime is 9661684751. The reversal of 9661684691 is 1964861669.

It is a weak prime.

It is an emirp because it is prime and its reverse (1964861669) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9661684691 - 2¹⁰ = 9661683667 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (9661684651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4830842345 + 4830842346.

It is an arithmetic number, because the mean of its divisors is an integer number (4830842346).

Almost surely, 2^9661684691 is an apocalyptic number.

9661684691 is a deficient number, since it is larger than the sum of its proper divisors (1).

9661684691 is an equidigital number, since it uses as much as digits as its factorization.

9661684691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3359232, while the sum is 56.

The square root of 9661684691 is about 98293.8690407494. The cubic root of 9661684691 is about 2129.8594903161.

The spelling of 9661684691 in words is "nine billion, six hundred sixty-one million, six hundred eighty-four thousand, six hundred ninety-one".