9991564227 has 12 divisors (see below), whose sum is σ = 14433413904. Its totient is φ = 6660510000.

The previous prime is 9991564183. The next prime is 9991564229. The reversal of 9991564227 is 7224651999.

9991564227 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9991564227 - 2¹⁴ = 9991547843 is a prime.

It is a super-2 number, since 2×9991564227² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (9991564229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 98602 + ... + 172352.

It is an arithmetic number, because the mean of its divisors is an integer number (1202784492).

Almost surely, 2^9991564227 is an apocalyptic number.

9991564227 is a deficient number, since it is larger than the sum of its proper divisors (4441849677).

9991564227 is a wasteful number, since it uses less digits than its factorization.

9991564227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88810 (or 88807 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The square root of 9991564227 is about 99957.8122359628. The cubic root of 9991564227 is about 2153.8287088697.

The spelling of 9991564227 in words is "nine billion, nine hundred ninety-one million, five hundred sixty-four thousand, two hundred twenty-seven".