2001991100 has 36 divisors (see below), whose sum is σ = 4351679808. Its totient is φ = 799440000.

The previous prime is 2001991081. The next prime is 2001991151. The reversal of 2001991100 is 11991002.

It is a congruent number.

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, 43445 + ... + 76755.

Almost surely, 2^2001991100 is an apocalyptic number.

2001991100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001991100 is an abundant number, since it is smaller than the sum of its proper divisors (2349688708).

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

2001991100 is a wasteful number, since it uses less digits than its factorization.

2001991100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33926 (or 33919 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 2001991100 is about 44743.6151869739. The cubic root of 2001991100 is about 1260.3390160239.

The spelling of 2001991100 in words is "two billion, one million, nine hundred ninety-one thousand, one hundred".