9891000221 has 8 divisors (see below), whose sum is σ = 10414466400. Its totient is φ = 9367822800.

The previous prime is 9891000193. The next prime is 9891000227. The reversal of 9891000221 is 1220001989.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9891000221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9891000227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11 + ... + 140648.

It is an arithmetic number, because the mean of its divisors is an integer number (1301808300).

Almost surely, 2^9891000221 is an apocalyptic number.

It is an amenable number.

9891000221 is a deficient number, since it is larger than the sum of its proper divisors (523466179).

9891000221 is a wasteful number, since it uses less digits than its factorization.

9891000221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144379.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 9891000221 is about 99453.5078365766. The cubic root of 9891000221 is about 2146.5783122265.

The spelling of 9891000221 in words is "nine billion, eight hundred ninety-one million, two hundred twenty-one", and thus it is an aban number.