2001209111 has 12 divisors (see below), whose sum is σ = 2319114840. Its totient is φ = 1712261760.

The previous prime is 2001209107. The next prime is 2001209117. The reversal of 2001209111 is 1119021002.

It is not a de Polignac number, because 2001209111 - 2² = 2001209107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 2001209111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001209117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 311576 + ... + 317933.

It is an arithmetic number, because the mean of its divisors is an integer number (193259570).

Almost surely, 2^2001209111 is an apocalyptic number.

2001209111 is a deficient number, since it is larger than the sum of its proper divisors (317905729).

2001209111 is a wasteful number, since it uses less digits than its factorization.

2001209111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 629554 (or 629537 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 2001209111 is about 44734.8757794185. The cubic root of 2001209111 is about 1260.1748961471.

It can be divided in two parts, 2001 and 209111, that added together give a palindrome (211112).

The spelling of 2001209111 in words is "two billion, one million, two hundred nine thousand, one hundred eleven".