9898921 has 2 divisors, whose sum is σ = 9898922. Its totient is φ = 9898920.

The previous prime is 9898907. The next prime is 9898979. The reversal of 9898921 is 1298989.

It is a happy number.

9898921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6528025 + 3370896 = 2555^2 + 1836^2 .

It is an emirp because it is prime and its reverse (1298989) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9898921 - 2⁷ = 9898793 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (9899921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4949460 + 4949461.

It is an arithmetic number, because the mean of its divisors is an integer number (4949461).

Almost surely, 2^9898921 is an apocalyptic number.

It is an amenable number.

9898921 is a deficient number, since it is larger than the sum of its proper divisors (1).

9898921 is an equidigital number, since it uses as much as digits as its factorization.

9898921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 46.

The square root of 9898921 is about 3146.2550754826. The cubic root of 9898921 is about 214.7151157421.

The spelling of 9898921 in words is "nine million, eight hundred ninety-eight thousand, nine hundred twenty-one".