991785994 has 8 divisors (see below), whose sum is σ = 1488040128. Its totient is φ = 495772620.

The previous prime is 991785983. The next prime is 991786009. The reversal of 991785994 is 499587199.

991785994 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49512 + ... + 66595.

It is an arithmetic number, because the mean of its divisors is an integer number (186005016).

Almost surely, 2^991785994 is an apocalyptic number.

991785994 is a deficient number, since it is larger than the sum of its proper divisors (496254134).

991785994 is a wasteful number, since it uses less digits than its factorization.

991785994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120380.

The product of its digits is 7348320, while the sum is 61.

The square root of 991785994 is about 31492.6339641510. The cubic root of 991785994 is about 997.2544669468.

The spelling of 991785994 in words is "nine hundred ninety-one million, seven hundred eighty-five thousand, nine hundred ninety-four".