9863921 has 4 divisors (see below), whose sum is σ = 10182144. Its totient is φ = 9545700.

The previous prime is 9863851. The next prime is 9863923. The reversal of 9863921 is 1293689.

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 an emirpimes, since its reverse is a distinct semiprime: 1293689 = 97 ⋅13337.

It is a cyclic number.

It is not a de Polignac number, because 9863921 - 2²² = 5669617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9863923) 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 3 ways as a sum of consecutive naturals, for example, 159065 + ... + 159126.

It is an arithmetic number, because the mean of its divisors is an integer number (2545536).

Almost surely, 2^9863921 is an apocalyptic number.

It is an amenable number.

9863921 is a deficient number, since it is larger than the sum of its proper divisors (318223).

9863921 is a wasteful number, since it uses less digits than its factorization.

9863921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318222.

The product of its digits is 23328, while the sum is 38.

The square root of 9863921 is about 3140.6879819555. The cubic root of 9863921 is about 214.4617580428.

The spelling of 9863921 in words is "nine million, eight hundred sixty-three thousand, nine hundred twenty-one".