20011121011111 has 4 divisors (see below), whose sum is σ = 20011136112000. Its totient is φ = 20011105910224.

The previous prime is 20011121011087. The next prime is 20011121011139. The reversal of 20011121011111 is 11111012111002.

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 20011121011111 - 2⁷ = 20011121010983 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20011121011091 and 20011121011100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011121011411) 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, 5348686 + ... + 8284363.

It is an arithmetic number, because the mean of its divisors is an integer number (5002784028000).

Almost surely, 2^{20011121011111} is an apocalyptic number.

20011121011111 is a deficient number, since it is larger than the sum of its proper divisors (15100889).

20011121011111 is a wasteful number, since it uses less digits than its factorization.

20011121011111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15100888.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 20011121011111 its reverse (11111012111002), we get a palindrome (31122133122113).

The spelling of 20011121011111 in words is "twenty trillion, eleven billion, one hundred twenty-one million, eleven thousand, one hundred eleven".