2001991011 has 8 divisors (see below), whose sum is σ = 2673721344. Its totient is φ = 1332460680.

The previous prime is 2001991003. The next prime is 2001991039. The reversal of 2001991011 is 1101991002.

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

It is not a de Polignac number, because 2001991011 - 2³ = 2001991003 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2001991081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 547875 + ... + 551516.

It is an arithmetic number, because the mean of its divisors is an integer number (334215168).

Almost surely, 2^2001991011 is an apocalyptic number.

2001991011 is a deficient number, since it is larger than the sum of its proper divisors (671730333).

2001991011 is a wasteful number, since it uses less digits than its factorization.

2001991011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100001.

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 2001991011 is about 44743.6141924186. The cubic root of 2001991011 is about 1260.3389973475.

Subtracting from 2001991011 its reverse (1101991002), we obtain a palindrome (900000009).

The spelling of 2001991011 in words is "two billion, one million, nine hundred ninety-one thousand, eleven".