20111220211211 has 4 divisors (see below), whose sum is σ = 20111232720912. Its totient is φ = 20111207701512.

The previous prime is 20111220211189. The next prime is 20111220211253. The reversal of 20111220211211 is 11211202211102.

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 20111220211211 - 2²⁶ = 20111153102347 is a prime.

It is a super-2 number, since 2×20111220211211² (a number of 27 digits) contains 22 as substring.

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 20111220211211.

It is not an unprimeable number, because it can be changed into a prime (20111220211711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3412976 + ... + 7202141.

It is an arithmetic number, because the mean of its divisors is an integer number (5027808180228).

Almost surely, 2^{20111220211211} is an apocalyptic number.

20111220211211 is a deficient number, since it is larger than the sum of its proper divisors (12509701).

20111220211211 is a wasteful number, since it uses less digits than its factorization.

20111220211211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12509700.

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

Adding to 20111220211211 its reverse (11211202211102), we get a palindrome (31322422422313).

The spelling of 20111220211211 in words is "twenty trillion, one hundred eleven billion, two hundred twenty million, two hundred eleven thousand, two hundred eleven".