9890021 has 8 divisors (see below), whose sum is σ = 10061688. Its totient is φ = 9720000.

The previous prime is 9890017. The next prime is 9890033. The reversal of 9890021 is 1200989.

It can be written as a sum of positive squares in 4 ways, for example, as 829921 + 9060100 = 911^2 + 3010^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9890021 - 2² = 9890017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9890011) 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 in 7 ways as a sum of consecutive naturals, for example, 18011 + ... + 18551.

It is an arithmetic number, because the mean of its divisors is an integer number (1257711).

Almost surely, 2^9890021 is an apocalyptic number.

It is an amenable number.

9890021 is a deficient number, since it is larger than the sum of its proper divisors (171667).

9890021 is a wasteful number, since it uses less digits than its factorization.

9890021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 9890021 is about 3144.8403775073. The cubic root of 9890021 is about 214.6507471938.

The spelling of 9890021 in words is "nine million, eight hundred ninety thousand, twenty-one".