9789867021 has 64 divisors (see below), whose sum is σ = 15527116800. Its totient is φ = 5422737600.

The previous prime is 9789867013. The next prime is 9789867041. The reversal of 9789867021 is 1207689879.

It is not a de Polignac number, because 9789867021 - 2³ = 9789867013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9789867001) 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 63 ways as a sum of consecutive naturals, for example, 2089960 + ... + 2094638.

It is an arithmetic number, because the mean of its divisors is an integer number (242611200).

Almost surely, 2^9789867021 is an apocalyptic number.

It is an amenable number.

9789867021 is a deficient number, since it is larger than the sum of its proper divisors (5737249779).

9789867021 is a wasteful number, since it uses less digits than its factorization.

9789867021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4830.

The product of its (nonzero) digits is 3048192, while the sum is 57.

The square root of 9789867021 is about 98943.7568571155. The cubic root of 9789867021 is about 2139.2371448262.

The spelling of 9789867021 in words is "nine billion, seven hundred eighty-nine million, eight hundred sixty-seven thousand, twenty-one".