991100100 has 36 divisors (see below), whose sum is σ = 2867583824. Its totient is φ = 264293280.

The previous prime is 991100083. The next prime is 991100111. The reversal of 991100100 is 1001199.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1651534 + ... + 1652133.

Almost surely, 2^991100100 is an apocalyptic number.

It is an amenable number.

991100100 is an abundant number, since it is smaller than the sum of its proper divisors (1876483724).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

991100100 is a wasteful number, since it uses less digits than its factorization.

991100100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3303684 (or 3303677 counting only the distinct ones).

The product of its (nonzero) digits is 81, while the sum is 21.

The square root of 991100100 is about 31481.7423278954. The cubic root of 991100100 is about 997.0245219783.

Adding to 991100100 its reverse (1001199), we get a palindrome (992101299).

The spelling of 991100100 in words is "nine hundred ninety-one million, one hundred thousand, one hundred".