2001111111 has 12 divisors (see below), whose sum is σ = 2917509192. Its totient is φ = 1321605456.

The previous prime is 2001111107. The next prime is 2001111121. The reversal of 2001111111 is 1111111002.

It is not a de Polignac number, because 2001111111 - 2² = 2001111107 is a prime.

It is a super-3 number, since 3×2001111111³ (a number of 29 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

2001111111 is a modest number, since divided by 111111 gives 2001 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 2001111093 and 2001111102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001111121) 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, 1038036 + ... + 1039961.

It is an arithmetic number, because the mean of its divisors is an integer number (243125766).

Almost surely, 2^2001111111 is an apocalyptic number.

2001111111 is a deficient number, since it is larger than the sum of its proper divisors (916398081).

2001111111 is a wasteful number, since it uses less digits than its factorization.

2001111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2078110 (or 2078107 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

The square root of 2001111111 is about 44733.7804237469. The cubic root of 2001111111 is about 1260.1543253907.

Adding to 2001111111 its reverse (1111111002), we get a palindrome (3112222113).

The spelling of 2001111111 in words is "two billion, one million, one hundred eleven thousand, one hundred eleven".