9888821 has 4 divisors (see below), whose sum is σ = 9895200. Its totient is φ = 9882444.

The previous prime is 9888817. The next prime is 9888841. The reversal of 9888821 is 1288889.

9888821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 9888821 - 2² = 9888817 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9888841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 800 + ... + 4518.

It is an arithmetic number, because the mean of its divisors is an integer number (2473800).

Almost surely, 2^9888821 is an apocalyptic number.

It is an amenable number.

9888821 is a deficient number, since it is larger than the sum of its proper divisors (6379).

9888821 is a wasteful number, since it uses less digits than its factorization.

9888821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6378.

The product of its digits is 73728, while the sum is 44.

The square root of 9888821 is about 3144.6495830219. The cubic root of 9888821 is about 214.6420653344.

The spelling of 9888821 in words is "nine million, eight hundred eighty-eight thousand, eight hundred twenty-one".