9816021 has 12 divisors (see below), whose sum is σ = 15012972. Its totient is φ = 6158976.

The previous prime is 9815999. The next prime is 9816029. The reversal of 9816021 is 1206189.

It can be written as a sum of positive squares in 2 ways, for example, as 8468100 + 1347921 = 2910^2 + 1161^2 .

It is not a de Polignac number, because 9816021 - 2⁷ = 9815893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9816029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31926 + ... + 32231.

It is an arithmetic number, because the mean of its divisors is an integer number (1251081).

Almost surely, 2^9816021 is an apocalyptic number.

It is an amenable number.

9816021 is a deficient number, since it is larger than the sum of its proper divisors (5196951).

9816021 is a wasteful number, since it uses less digits than its factorization.

9816021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64180 (or 64177 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 9816021 is about 3133.0529839120. The cubic root of 9816021 is about 214.1140467017.

The spelling of 9816021 in words is "nine million, eight hundred sixteen thousand, twenty-one".