991818472 has 16 divisors (see below), whose sum is σ = 1861121700. Its totient is φ = 495519360.

The previous prime is 991818469. The next prime is 991818491. The reversal of 991818472 is 274818199.

It can be written as a sum of positive squares in 2 ways, for example, as 736905316 + 254913156 = 27146^2 + 15966^2 .

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, 37779 + ... + 58402.

Almost surely, 2^991818472 is an apocalyptic number.

It is an amenable number.

991818472 is a deficient number, since it is larger than the sum of its proper divisors (869303228).

991818472 is a wasteful number, since it uses less digits than its factorization.

991818472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97476 (or 97472 counting only the distinct ones).

The product of its digits is 290304, while the sum is 49.

The square root of 991818472 is about 31493.1496043187. The cubic root of 991818472 is about 997.2653525200.

The spelling of 991818472 in words is "nine hundred ninety-one million, eight hundred eighteen thousand, four hundred seventy-two".