9665439491 has 2 divisors, whose sum is σ = 9665439492. Its totient is φ = 9665439490.

The previous prime is 9665439467. The next prime is 9665439527. The reversal of 9665439491 is 1949345669.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9665439491 is a prime.

It is not a weakly prime, because it can be changed into another prime (9665439991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4832719745 + 4832719746.

It is an arithmetic number, because the mean of its divisors is an integer number (4832719746).

Almost surely, 2^9665439491 is an apocalyptic number.

9665439491 is a deficient number, since it is larger than the sum of its proper divisors (1).

9665439491 is an equidigital number, since it uses as much as digits as its factorization.

9665439491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6298560, while the sum is 56.

The square root of 9665439491 is about 98312.9670541989. The cubic root of 9665439491 is about 2130.1353621720.

The spelling of 9665439491 in words is "nine billion, six hundred sixty-five million, four hundred thirty-nine thousand, four hundred ninety-one".