9821211863 has 4 divisors (see below), whose sum is σ = 9821587440. Its totient is φ = 9820836288.

The previous prime is 9821211847. The next prime is 9821211871. The reversal of 9821211863 is 3681121289.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9821211863 - 2⁴ = 9821211847 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9821211863.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9821211563) 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, 145370 + ... + 201927.

It is an arithmetic number, because the mean of its divisors is an integer number (2455396860).

Almost surely, 2^9821211863 is an apocalyptic number.

9821211863 is a deficient number, since it is larger than the sum of its proper divisors (375577).

9821211863 is a wasteful number, since it uses less digits than its factorization.

9821211863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375576.

The product of its digits is 41472, while the sum is 41.

The square root of 9821211863 is about 99102.0275423263. The cubic root of 9821211863 is about 2141.5178231861.

The spelling of 9821211863 in words is "nine billion, eight hundred twenty-one million, two hundred eleven thousand, eight hundred sixty-three".