20011121222111 has 4 divisors (see below), whose sum is σ = 20015939699952. Its totient is φ = 20006302744272.

The previous prime is 20011121222003. The next prime is 20011121222123. The reversal of 20011121222111 is 11122212111002.

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 20011121222111 - 2³⁰ = 20010047480287 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20011121222111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011121222611) 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, 2409232691 + ... + 2409240996.

It is an arithmetic number, because the mean of its divisors is an integer number (5003984924988).

Almost surely, 2^{20011121222111} is an apocalyptic number.

20011121222111 is a deficient number, since it is larger than the sum of its proper divisors (4818477841).

20011121222111 is an equidigital number, since it uses as much as digits as its factorization.

20011121222111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4818477840.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 20011121222111 its reverse (11122212111002), we get a palindrome (31133333333113).

It can be divided in two parts, 2001112 and 1222111, that added together give a palindrome (3223223).

The spelling of 20011121222111 in words is "twenty trillion, eleven billion, one hundred twenty-one million, two hundred twenty-two thousand, one hundred eleven".