2001121111 has 6 divisors (see below), whose sum is σ = 2199579536. Its totient is φ = 1819200900.

The previous prime is 2001121099. The next prime is 2001121117. The reversal of 2001121111 is 1111211002.

It is not a de Polignac number, because 2001121111 - 2¹⁷ = 2000990039 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001121117) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8268975 + ... + 8269216.

Almost surely, 2^2001121111 is an apocalyptic number.

2001121111 is a deficient number, since it is larger than the sum of its proper divisors (198458425).

2001121111 is a wasteful number, since it uses less digits than its factorization.

2001121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16538213 (or 16538202 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

The square root of 2001121111 is about 44733.8921959626. The cubic root of 2001121111 is about 1260.1564244782.

Adding to 2001121111 its reverse (1111211002), we get a palindrome (3112332113).

The spelling of 2001121111 in words is "two billion, one million, one hundred twenty-one thousand, one hundred eleven".