9991916 has 12 divisors (see below), whose sum is σ = 19075560. Its totient is φ = 4541760.

The previous prime is 9991879. The next prime is 9991939. The reversal of 9991916 is 6191999.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (44), and also a Moran number because the ratio is a prime number: 227089 = 9991916 / (9 + 9 + 9 + 1 + 9 + 1 + 6).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113501 + ... + 113588.

It is an arithmetic number, because the mean of its divisors is an integer number (1589630).

Almost surely, 2^9991916 is an apocalyptic number.

It is an amenable number.

9991916 is a deficient number, since it is larger than the sum of its proper divisors (9083644).

9991916 is a wasteful number, since it uses less digits than its factorization.

9991916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227104 (or 227102 counting only the distinct ones).

The product of its digits is 39366, while the sum is 44.

The square root of 9991916 is about 3160.9992091109. Note that the first 3 decimals coincide. The cubic root of 9991916 is about 215.3853985189.

The spelling of 9991916 in words is "nine million, nine hundred ninety-one thousand, nine hundred sixteen".