9805824021 has 16 divisors (see below), whose sum is σ = 14953895424. Its totient is φ = 5598945264.

The previous prime is 9805824001. The next prime is 9805824023. The reversal of 9805824021 is 1204285089.

It is not a de Polignac number, because 9805824021 - 2⁶ = 9805823957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9805824023) 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 15 ways as a sum of consecutive naturals, for example, 155031 + ... + 208916.

It is an arithmetic number, because the mean of its divisors is an integer number (934618464).

Almost surely, 2^9805824021 is an apocalyptic number.

It is an amenable number.

9805824021 is a deficient number, since it is larger than the sum of its proper divisors (5148071403).

9805824021 is a wasteful number, since it uses less digits than its factorization.

9805824021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365240.

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 9805824021 is about 99024.3607452227. The cubic root of 9805824021 is about 2140.3987975590.

The spelling of 9805824021 in words is "nine billion, eight hundred five million, eight hundred twenty-four thousand, twenty-one".