21120220111211 has 24 divisors (see below), whose sum is σ = 24006021049584. Its totient is φ = 18468684054720.

The previous prime is 21120220111189. The next prime is 21120220111273. The reversal of 21120220111211 is 11211102202112.

It is a de Polignac number, because none of the positive numbers 2^k-21120220111211 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 21120220111211.

It is not an unprimeable number, because it can be changed into a prime (21120220110211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 121306841 + ... + 121480821.

It is an arithmetic number, because the mean of its divisors is an integer number (1000250877066).

Almost surely, 2^{21120220111211} is an apocalyptic number.

21120220111211 is a deficient number, since it is larger than the sum of its proper divisors (2885800938373).

21120220111211 is a wasteful number, since it uses less digits than its factorization.

21120220111211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199899 (or 199880 counting only the distinct ones).

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

Adding to 21120220111211 its reverse (11211102202112), we get a palindrome (32331322313323).

The spelling of 21120220111211 in words is "twenty-one trillion, one hundred twenty billion, two hundred twenty million, one hundred eleven thousand, two hundred eleven".