9863721 has 16 divisors (see below), whose sum is σ = 16700800. Its totient is φ = 5636304.

The previous prime is 9863713. The next prime is 9863729. The reversal of 9863721 is 1273689.

It is an interprime number because it is at equal distance from previous prime (9863713) and next prime (9863729).

It is not a de Polignac number, because 9863721 - 2³ = 9863713 is a prime.

It is a Duffinian number.

9863721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9863729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25906 + ... + 26283.

It is an arithmetic number, because the mean of its divisors is an integer number (1043800).

Almost surely, 2^9863721 is an apocalyptic number.

It is an amenable number.

9863721 is a deficient number, since it is larger than the sum of its proper divisors (6837079).

9863721 is a wasteful number, since it uses less digits than its factorization.

9863721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52205 (or 52199 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 9863721 is about 3140.6561416366. The cubic root of 9863721 is about 214.4603085638.

The spelling of 9863721 in words is "nine million, eight hundred sixty-three thousand, seven hundred twenty-one".