9991080215 has 16 divisors (see below), whose sum is σ = 12377175168. Its totient is φ = 7736518656.

The previous prime is 9991080199. The next prime is 9991080227. The reversal of 9991080215 is 5120801999.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 9991080215 - 2⁴ = 9991080199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104207 + ... + 175616.

It is an arithmetic number, because the mean of its divisors is an integer number (773573448).

Almost surely, 2^9991080215 is an apocalyptic number.

9991080215 is a deficient number, since it is larger than the sum of its proper divisors (2386094953).

9991080215 is a wasteful number, since it uses less digits than its factorization.

9991080215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280058.

The product of its (nonzero) digits is 58320, while the sum is 44.

The square root of 9991080215 is about 99955.3911252415. The cubic root of 9991080215 is about 2153.7939296716.

The spelling of 9991080215 in words is "nine billion, nine hundred ninety-one million, eighty thousand, two hundred fifteen".