991848799922 has 6 divisors (see below), whose sum is σ = 1487775312543. Its totient is φ = 495923695742.

The previous prime is 991848799889. The next prime is 991848799927. The reversal of 991848799922 is 229997848199.

It can be written as a sum of positive squares in only one way, i.e., 495924399961 + 495924399961 = 704219^2 + 704219^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=704219.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991848799927) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1056329 + ... + 1760547.

Almost surely, 2^991848799922 is an apocalyptic number.

991848799922 is a deficient number, since it is larger than the sum of its proper divisors (495926512621).

991848799922 is an frugal number, since it uses more digits than its factorization.

991848799922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408440 (or 704221 counting only the distinct ones).

The product of its digits is 423263232, while the sum is 77.

The spelling of 991848799922 in words is "nine hundred ninety-one billion, eight hundred forty-eight million, seven hundred ninety-nine thousand, nine hundred twenty-two".