9678821 has 2 divisors, whose sum is σ = 9678822. Its totient is φ = 9678820.

The previous prime is 9678787. The next prime is 9678833. The reversal of 9678821 is 1288769.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9541921 + 136900 = 3089^2 + 370^2 .

It is an emirp because it is prime and its reverse (1288769) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9678821 - 2¹⁴ = 9662437 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9678841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4839410 + 4839411.

It is an arithmetic number, because the mean of its divisors is an integer number (4839411).

Almost surely, 2^9678821 is an apocalyptic number.

It is an amenable number.

9678821 is a deficient number, since it is larger than the sum of its proper divisors (1).

9678821 is an equidigital number, since it uses as much as digits as its factorization.

9678821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 41.

The square root of 9678821 is about 3111.0803589750. The cubic root of 9678821 is about 213.1117944880. Note that the first 3 decimals are identical.

The spelling of 9678821 in words is "nine million, six hundred seventy-eight thousand, eight hundred twenty-one".