991618916 has 12 divisors (see below), whose sum is σ = 1737751680. Its totient is φ = 495118440.

The previous prime is 991618897. The next prime is 991618937. The reversal of 991618916 is 619816199.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 169520 + ... + 175271.

It is an arithmetic number, because the mean of its divisors is an integer number (144812640).

Almost surely, 2^991618916 is an apocalyptic number.

It is an amenable number.

991618916 is a deficient number, since it is larger than the sum of its proper divisors (746132764).

991618916 is a wasteful number, since it uses less digits than its factorization.

991618916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345514 (or 345512 counting only the distinct ones).

The product of its digits is 209952, while the sum is 50.

The square root of 991618916 is about 31489.9812003755. The cubic root of 991618916 is about 997.1984640591.

The spelling of 991618916 in words is "nine hundred ninety-one million, six hundred eighteen thousand, nine hundred sixteen".