9822721 has 2 divisors, whose sum is σ = 9822722. Its totient is φ = 9822720.

The previous prime is 9822653. The next prime is 9822727. The reversal of 9822721 is 1272289.

It is the 1280-th star number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9678321 + 144400 = 3111^2 + 380^2 .

It is an emirp because it is prime and its reverse (1272289) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9822721 - 2¹⁵ = 9789953 is a prime.

It is not a weakly prime, because it can be changed into another prime (9822727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4911360 + 4911361.

It is an arithmetic number, because the mean of its divisors is an integer number (4911361).

Almost surely, 2^9822721 is an apocalyptic number.

It is an amenable number.

9822721 is a deficient number, since it is larger than the sum of its proper divisors (1).

9822721 is an equidigital number, since it uses as much as digits as its factorization.

9822721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 31.

The square root of 9822721 is about 3134.1220461239. The cubic root of 9822721 is about 214.1627506808.

The spelling of 9822721 in words is "nine million, eight hundred twenty-two thousand, seven hundred twenty-one".