9668821 has 2 divisors, whose sum is σ = 9668822. Its totient is φ = 9668820.

The previous prime is 9668819. The next prime is 9668833. The reversal of 9668821 is 1288669.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8346321 + 1322500 = 2889^2 + 1150^2 .

It is a cyclic number.

It is not a de Polignac number, because 9668821 - 2¹ = 9668819 is a prime.

Together with 9668819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9668881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4834410 + 4834411.

It is an arithmetic number, because the mean of its divisors is an integer number (4834411).

Almost surely, 2^9668821 is an apocalyptic number.

It is an amenable number.

9668821 is a deficient number, since it is larger than the sum of its proper divisors (1).

9668821 is an equidigital number, since it uses as much as digits as its factorization.

9668821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 40.

The square root of 9668821 is about 3109.4727848946. The cubic root of 9668821 is about 213.0383746533.

The spelling of 9668821 in words is "nine million, six hundred sixty-eight thousand, eight hundred twenty-one".