201111121111111 has 4 divisors (see below), whose sum is σ = 201421957465872. Its totient is φ = 200800284756352.

The previous prime is 201111121111099. The next prime is 201111121111141. The reversal of 201111121111111 is 111111121111102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201111121111111 - 2²⁵ = 201111087556679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201111121111141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155418176410 + ... + 155418177703.

It is an arithmetic number, because the mean of its divisors is an integer number (50355489366468).

Almost surely, 2^{201111121111111} is an apocalyptic number.

201111121111111 is a deficient number, since it is larger than the sum of its proper divisors (310836354761).

201111121111111 is an equidigital number, since it uses as much as digits as its factorization.

201111121111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310836354760.

The product of its (nonzero) digits is 4, while the sum is 16.

Adding to 201111121111111 its reverse (111111121111102), we get a palindrome (312222242222213).

Subtracting from 201111121111111 its reverse (111111121111102), we obtain a palindrome (90000000000009).

The spelling of 201111121111111 in words is "two hundred one trillion, one hundred eleven billion, one hundred twenty-one million, one hundred eleven thousand, one hundred eleven".