9872021 has 12 divisors (see below), whose sum is σ = 10427340. Its totient is φ = 9339840.

The previous prime is 9872017. The next prime is 9872047. The reversal of 9872021 is 1202789.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 3189796 + 6682225 = 1786^2 + 2585^2 .

It is not a de Polignac number, because 9872021 - 2² = 9872017 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 (9872011) 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 in 11 ways as a sum of consecutive naturals, for example, 90515 + ... + 90623.

It is an arithmetic number, because the mean of its divisors is an integer number (868945).

Almost surely, 2^9872021 is an apocalyptic number.

It is an amenable number.

9872021 is a deficient number, since it is larger than the sum of its proper divisors (555319).

9872021 is a wasteful number, since it uses less digits than its factorization.

9872021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 9872021 is about 3141.9772437114. The cubic root of 9872021 is about 214.5204454877.

The spelling of 9872021 in words is "nine million, eight hundred seventy-two thousand, twenty-one".