9663581 has 2 divisors, whose sum is σ = 9663582. Its totient is φ = 9663580.

The previous prime is 9663553. The next prime is 9663587. The reversal of 9663581 is 1853669.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8791225 + 872356 = 2965^2 + 934^2 .

It is an emirp because it is prime and its reverse (1853669) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9663581 is a prime.

It is a super-2 number, since 2×9663581² = 186769595487122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9663587) 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, 4831790 + 4831791.

It is an arithmetic number, because the mean of its divisors is an integer number (4831791).

Almost surely, 2^9663581 is an apocalyptic number.

It is an amenable number.

9663581 is a deficient number, since it is larger than the sum of its proper divisors (1).

9663581 is an equidigital number, since it uses as much as digits as its factorization.

9663581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 38.

The square root of 9663581 is about 3108.6300841367. The cubic root of 9663581 is about 212.9998824454. Note that the first 3 decimals are identical.

The spelling of 9663581 in words is "nine million, six hundred sixty-three thousand, five hundred eighty-one".